Conductive member, touch sensor and touch panel

ABSTRACT

A conductive sheet, method for using conductive sheet and touch panel, having a base substance and conductive parts formed on one of the principal surfaces of the base substance. The conductive parts respectively extend in primary directions, and have two or more conductive patterns made from metal wires arranged in a second direction that is perpendicular to the first direction. The conductive pattern is constituted by serially connecting two or more large gratings in the first direction, and each of the large gratings is constituted by combining two or more small gratings. Around the edges of the large grating, non-connective patterns are formed from metal wires which are not connected with the large gratings.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation patent application of U.S.patent application Ser. No. 15/591,734, filed May 10, 2017, which is acontinuation patent application of U.S. patent application Ser. No.14/539,666, filed Nov. 12, 2014, now U.S. Pat. No. 9,684,423, issued onJun. 20, 2017, which is a divisional patent application of U.S. patentapplication Ser. No. 13/576,135 filed Jul. 30, 2012, now U.S. Pat. No.8,917,252, issued on Dec. 23, 2014, which is a 35 U.S.C. 371 NationalStage Entry of PCT/JP2011/051692, filed Jan. 28, 2011, which claimspriority from Japanese Patent Application Nos. 2010-017293, filed onJan. 28, 2010, 2010-105865, filed on Apr. 30, 2010, 2010-153232, filedon Jul. 5, 2010, and 2010-281465, filed on Dec. 17, 2010, the contentsof all of which are herein incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a conductive sheet, a method for usinga conductive sheet, and a touch panel, and for example to a conductivesheet suitable for use in a projected capacitive touch panel, a methodfor using a conductive sheet, and a touch panel.

BACKGROUND ART

Touch panels have attracted much attention in recent years. For example,a touch panel, which uses ITO (indium tin oxide) as an electrodematerial to form a less-visible electrode matrix, has been disclosed(see, Japanese Laid-Open Patent Publication Nos. 2008-129708 and05-224818, etc.)

Though the touch panels have currently been used mainly in small devicessuch as PDAs (personal digital assistants) and mobile phones, they areexpected to be used in larger devices such as personal computerdisplays.

The above electrode is composed of the ITO (indium tin oxide) andtherefore has a high resistance. Thus, when the conventional touch panelis used in the larger device in the above future trend, the large-sizedtouch panel disadvantageously has a low current transfer rate betweenthe electrodes and thereby exhibits a low response speed (a long timebetween finger contact and touch position detection).

A large number of lattices composed of thin wires of a metal (thin metalwires) can be arranged to form an electrode with a lowered surfaceresistance. A touch panel using the electrode of the thin metal wires isknown from U.S. Pat. No. 5,113,041, International Patent Publication No.95/027334, US Patent Application Publication No. 2004/0239650, U.S. Pat.No. 7,202,859, International Patent Publication No. 97/018508, andJapanese Laid-Open Patent Publication No. 2003-099185, etc.

SUMMARY OF INVENTION

However, in the case of using the thin metal wires for the electrode,the thin metal wires are composed of an opaque material, whereby theelectrode has problems of transparency and visibility.

In view of the problems, an object of the present invention is toprovide a conductive sheet, which can have a conductive pattern with alowered resistance, can exhibit an improved visibility, and can besuitably used in a projected capacitive touch panel or the like, and amethod for using the conductive sheet.

Another object of the present invention is to provide a touch panel,which can have a conductive pattern with a lowered resistance, canexhibit an improved visibility, and can be adapted as a large-sizedprojected capacitive touch panel or the like.

[1] A conductive sheet according to a first aspect of the presentinvention, comprising two or more conductive first large latticescomposed of a thin metal wire formed on one main surface of a substrateand two or more conductive second large lattices composed of a thinmetal wire formed on the other main surface of the substrate, whereinthe first and second large lattices each contain a combination of two ormore small lattices, a first unconnected pattern composed of a thinmetal wire separated from the first large lattices is formed around aside of the first large lattices, a second unconnected pattern composedof a thin metal wire separated from the second large lattices is formedaround a side of the second large lattices, the first large lattices arearranged adjacent to the second large lattices as viewed from above, thefirst and second unconnected patterns overlap with each other to form acombined pattern between the first and second large lattices, and thecombined pattern has a pattern approximately equal to inner patterns ofthe first and second large lattices.

[2] A conductive sheet according to a second aspect of the presentinvention for a touch panel to be placed on a display panel of a displaydevice, comprising first and second conductive sheets, wherein the firstconductive sheet contains a first substrate and a first conductive partformed on a main surface of the first substrate, the second conductivesheet contains a second substrate and a second conductive part formed ona main surface of the second substrate, the first conductive sheet isstacked on the second conductive sheet, the first conductive partcontains two or more first conductive patterns composed of a thin metalwire, the first conductive patterns each extend in a first direction andare arranged in a second direction perpendicular to the first direction,the second conductive part contains two or more second conductivepatterns composed of a thin metal wire, the second conductive patternseach extend in the second direction and are arranged in the firstdirection, the first conductive patterns each contain two or more firstlarge lattices arranged in the first direction, the second conductivepatterns each contain two or more second large lattices arranged in thesecond direction, a first unconnected pattern composed of a thin metalwire separated from the first large lattices is formed around a side ofthe first large lattices, a second unconnected pattern composed of athin metal wire separated from the second large lattices is formedaround a side of the second large lattices, the first large lattices arearranged adjacent to the second large lattices as viewed from above, thefirst and second unconnected patterns overlap with each other to form acombined pattern between the first and second large lattices, and thecombined pattern contains a combination of two or more small lattices.

[3] A conductive sheet according to a third aspect of the presentinvention, comprising a substrate, a first conductive part formed on onemain surface of the substrate, and a second conductive part formed onthe other main surface of the substrate, wherein the first conductivepart contains two or more first conductive patterns, the firstconductive patterns each extend in a first direction and are arranged ina second direction perpendicular to the first direction, the secondconductive part contains two or more second conductive patterns, thesecond conductive patterns each extend in the second direction and arearranged in the first direction, and the first and second conductivepatterns are crossed and displaced in a direction different from thefirst and second directions as viewed from above.

[4] A conductive sheet according to a fourth aspect of the presentinvention, comprising a substrate, a first conductive part formed on onemain surface of the substrate, and a second conductive part formed onthe other main surface of the substrate, wherein the first conductivepart contains two or more first conductive patterns and a first dummypattern, the first conductive patterns each extend in a first directionand are arranged in a second direction perpendicular to the firstdirection, the first dummy pattern contains a plurality of firstauxiliary wires arranged around the first conductive patterns, thesecond conductive part contains two or more second transparentconductive patterns and a second dummy pattern, the second transparentconductive patterns each extend in the second direction and are arrangedin the first direction, the second dummy pattern contains a plurality ofsecond auxiliary wires arranged around the second transparent conductivepatterns, the first and second transparent conductive patterns arecrossed as viewed from above, the first and second dummy patternsoverlap with each other to form a combined pattern between the first andsecond transparent conductive patterns, and the first and secondauxiliary wires are not perpendicularly crossed in the combined pattern.

[5] A method for using a conductive sheet according to a fifth aspect ofthe present invention, comprising using first and second conductivesheets, wherein the first conductive sheet contains two or moreconductive first large lattices composed of a thin metal wire, the firstlarge lattices each contain a combination of two or more small lattices,the second conductive sheet contains two or more conductive second largelattices composed of a thin metal wire, the second large lattices eachcontain a combination of two or more of the small lattices, a firstunconnected pattern composed of a thin metal wire separated from thefirst large lattices is formed around a side of the first largelattices, a second unconnected pattern composed of a thin metal wireseparated from the second large lattices is formed around a side of thesecond large lattices, and the first and second conductive sheets arecombined, so that the first large lattices are arranged adjacent to thesecond large lattices, and the first and second unconnected patterns arecombined to form an arrangement of the small lattices.

[6] A touch panel according to a sixth aspect of the present invention,comprising a touch panel conductive sheet, wherein the touch panelconductive sheet contains a substrate and a conductive part formed onone main surface of the substrate, the conductive part contains two ormore conductive patterns composed of a thin metal wire, the conductivepatterns each extend in a first direction and are arranged in a seconddirection perpendicular to the first direction, the conductive patternseach contain two or more large lattices connected in series in the firstdirection, the large lattices each contain a combination of two or moresmall lattices, and a first unconnected pattern composed of a thin metalwire separated from the large lattices is formed around a side of thefirst large lattices.

[7] A touch panel according to a seventh aspect of the presentinvention, comprising a touch panel conductive sheet, wherein the touchpanel conductive sheet contains a substrate, a first conductive partformed on one main surface of the substrate, and a second conductivepart formed on the other main surface of the substrate, the firstconductive part contains two or more first transparent conductivepatterns, the first transparent conductive patterns each extend in afirst direction and are arranged in a second direction perpendicular tothe first direction, the second conductive part contains two or moresecond transparent conductive patterns, the second transparentconductive patterns each extend in the second direction and are arrangedin the first direction, and the first and second transparent conductivepatterns are crossed and displaced in a direction different from thefirst and second directions as viewed from above.

[8] A touch panel according to an eighth aspect of the presentinvention, comprising a touch panel conductive sheet, wherein the touchpanel conductive sheet contains a substrate, a first conductive partformed on one main surface of the substrate, and a second conductivepart formed on the other main surface of the substrate, the firstconductive part contains two or more first transparent conductivepatterns and a first dummy pattern, the first transparent conductivepatterns each extend in a first direction and are arranged in a seconddirection perpendicular to the first direction, the first dummy patterncontains a plurality of first auxiliary wires arranged around the firsttransparent conductive patterns, the second conductive part contains twoor more second transparent conductive patterns and a second dummypattern, the second transparent conductive patterns each extend in thesecond direction and are arranged in the first direction, the seconddummy pattern contains a plurality of second auxiliary wires arrangedaround the second transparent conductive patterns, the first and secondtransparent conductive patterns are crossed as viewed from above, thefirst and second dummy patterns overlap with each other to form acombined pattern between the first and second transparent conductivepatterns, and the first and second auxiliary wires are notperpendicularly crossed in the combined pattern.

As described above, in the conductive sheet and the conductive sheetusing method of the present invention, the conductive pattern formed onthe substrate can exhibit a lowered resistance and an improvedvisibility, and the conductive sheet can be suitably used in a projectedcapacitive touch panel or the like.

Furthermore, in the touch panel of the present invention, the conductivepattern formed on the substrate can exhibit a lowered resistance and animproved visibility, and the touch panel can be used as a large-sizedprojected capacitive touch panel or the like.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view showing a pattern example of a first conductivepattern formed on a first conductive sheet;

FIG. 2 is a cross-sectional view partially showing the first conductivesheet;

FIG. 3 is an exploded perspective view showing a structure of a touchpanel;

FIG. 4 is an exploded perspective view partially showing a firstlaminated conductive sheet;

FIG. 5A is a cross-sectional view partially showing an example of thelaminated conductive sheet;

FIG. 5B is a cross-sectional view partially showing another example ofthe laminated conductive sheet;

FIG. 6 is a plan view showing a pattern example of a second conductivepattern formed on a second conductive sheet in the first laminatedconductive sheet;

FIG. 7 is a plan view partially showing an example of the firstlaminated conductive sheet obtained by combining the first and secondconductive sheets;

FIG. 8A is a schematic view showing a first structure example using anantireflection film;

FIG. 8B is a schematic view showing a second structure example using asimilar film;

FIG. 8C is a schematic view showing a third structure example using asimilar film;

FIG. 9 is an exploded perspective view partially showing a secondlaminated conductive sheet;

FIG. 10 is a plan view showing a pattern example of a first conductivepattern formed on a first conductive sheet in the second laminatedconductive sheet;

FIG. 11 is a plan view showing a pattern example of a second conductivepattern formed on a second conductive sheet in the second laminatedconductive sheet;

FIG. 12 is a plan view partially showing an example of the secondlaminated conductive sheet obtained by combining the first and secondconductive sheets;

FIG. 13 is an exploded perspective view partially showing a thirdlaminated conductive sheet;

FIG. 14 is a plan view showing a pattern example of a first conductivepattern formed on a first conductive sheet in the third laminatedconductive sheet;

FIG. 15 is a plan view showing a pattern example of a second conductivepattern formed on a second conductive sheet in the third laminatedconductive sheet;

FIG. 16 is a plan view partially showing an example of the thirdlaminated conductive sheet obtained by combining the first and secondconductive sheets;

FIG. 17 is an exploded perspective view partially showing a fourthlaminated conductive sheet;

FIG. 18A is a cross-sectional view partially showing an example of thefourth laminated conductive sheet, and FIG. 18B is a cross-sectionalview partially showing another example of the fourth laminatedconductive sheet;

FIG. 19 is a plan view showing a pattern example of a first conductivepart formed on a first conductive sheet in the fourth laminatedconductive sheet;

FIG. 20 is a plan view showing a pattern example of a second conductivepart formed on a second conductive sheet in the fourth laminatedconductive sheet;

FIG. 21 is a plan view partially showing an example of the fourthlaminated conductive sheet obtained by combining the first and secondconductive sheets;

FIG. 22 is an explanatory view showing a line formed by first and secondauxiliary wires;

FIG. 23 is a plan view partially showing another example of the fourthlaminated conductive sheet obtained by combining the first and secondconductive sheets;

FIGS. 24A to 24C are each an explanatory view showing an example of acombination of a first auxiliary wire arranged along a side of a firstlarge lattice and a second auxiliary wire arranged along a side of asecond large lattice in a combined pattern;

FIG. 25 is an explanatory view showing an example of a combination offirst auxiliary wires in two first L-shaped patterns of a firstinsulation and second auxiliary wires in two second L-shaped patterns ofa second insulation in the combined pattern;

FIG. 26 is a flow chart of a method for producing a laminated conductivesheet according to an embodiment of the present invention;

FIG. 27A is a cross-sectional view partially showing a preparedphotosensitive material, and FIG. 27B is an explanatory view showing asimultaneous both-side exposure of the photosensitive material; and

FIG. 28 is an explanatory view showing first and second exposuretreatments performed such that a light incident on a firstphotosensitive layer does not reach a second photosensitive layer and alight incident on the second photosensitive layer does not reach thefirst photosensitive layer.

DESCRIPTION OF EMBODIMENTS

Several embodiments of the conductive sheet, the conductive sheet usingmethod, and the touch panel of the present invention will be describedbelow with reference to FIGS. 1 to 28. It should be noted that, in thisdescription, a numeric range of “A to B” includes both the numericvalues A and B as the lower limit and upper limit values.

A conductive sheet according to a first embodiment of the presentinvention (hereinafter referred to as the first conductive sheet 10A)will be described below with reference to FIGS. 1 and 2.

As shown in FIG. 1, the first conductive sheet 10A has a firstconductive part 13A formed on one main surface of a first transparentsubstrate 14A (see FIG. 2). The first conductive part 13A contains twoor more conductive first large lattices 16A composed of thin metal wires15, and each of the first large lattices 16A contains a combination oftwo or more small lattices 18. A first dummy pattern 20A (a firstunconnected pattern) composed of thin metal wires 15, separated from thefirst large lattices 16A, is formed around each side of the first largelattices 16A. A first connection 22A composed of thin metal wires 15 isformed between each adjacent two of the first large lattices 16A toelectrically connect the first large lattices 16A. The first connection22A contains one or more medium lattices 24 (24 a to 24 d), and thepitch of the medium lattices 24 is n times larger than that of the smalllattices 18 (in which n is a real number larger than 1). The smalllattices 18 have a smallest square shape in this embodiment. Forexample, the thin metal wires 15 contain gold (Au), silver (Ag), orcopper (Cu).

The side length of the first large lattice 16A is preferably 3 to 10 mm,more preferably 4 to 6 mm. If the side length is less than the lowerlimit, in the case of using the first conductive sheet 10A in a touchpanel or the like, the first large lattice 16A exhibits a loweredelectrostatic capacitance in a detection process, and the touch panel islikely to cause a detection trouble. On the other hand, if the sidelength is more than the upper limit, the position detection accuracy maybe deteriorated. The side length of each small lattice 18 in the firstlarge lattice 16A is preferably 50 to 500 μm, more preferably 150 to 300μm, for the same reasons. If the side length of the small lattice 18 iswithin this range, the first conductive sheet 10A can have excellenttransparency and thereby can be suitably used at the front of a displaydevice with excellent visibility without creating any feeling ofstrangeness.

The lower limit of the line width of the thin metal wire 15 ispreferably 1 μm or more, 3 μm or more, 4 μm or more, or 5 μm or more,and the upper limit thereof is preferably 15 μm or less, 10 μm or less,9 μm or less, or 8 μm or less. If the line width is less than the lowerlimit, the thin metal wire 15 has an insufficient conductivity, wherebya touch panel using the thin metal wire 15 has insufficient detectionsensitivity. On the other hand, if the line width is more than the upperlimit, a moire may be significantly generated due to the conductivemetal portion, and a touch panel using the thin metal wire 15 may have apoor visibility. If the line width is within the above range, the moireof the conductive metal portion is improved, and the visibility isremarkably improved.

Two or more of the first large lattices 16A are arranged in an xdirection (a first direction) with the first connection 22A disposedtherebetween to form one first conductive pattern 26A composed of thethin metal wires 15. Two or more of the first conductive patterns 26Aare arranged in a y direction (a second direction) perpendicular to thex direction, and electrically isolated first insulations 28A aredisposed between the adjacent first conductive patterns 26A.

For example, the x direction corresponds to the horizontal or verticaldirection of a projected capacitive touch panel 100 or a display panel110 equipped therewith to be hereinafter described (see FIG. 3).

As shown in FIG. 1, four sides 32 of the first large lattice 16A (i.e. afirst side 32 a and a second side 32 b on one corner 30 a unconnected tothe adjacent first large lattice 16A and a third side 32 c and a fourthside 32 d on the other corner 30 b unconnected to the adjacent firstlarge lattice 16A) each have a straight line shape. In other words, theintersection of the straight lines of the first side 32 a and the secondside 32 b corresponds to the one corner 30 a of the first large lattice16A, and the intersection of the straight lines of the third side 32 cand the fourth side 32 d corresponds to the other corner 30 b of thefirst large lattice 16A.

In the first connection 22A, the four medium lattices 24 (the firstmedium lattice 24 a to the fourth medium lattice 24 d) are arranged in azigzag manner, and each of the medium lattices 24 has a size equal tothe total of four small lattices 18. The first medium lattice 24 a isdisposed at the intersection of the second side 32 b and the fourth side32 d, and forms an L-shaped space in combination with one small lattice18. The second medium lattice 24 b is disposed on one side of the firstmedium lattice 24 a, and forms such a square space that four smalllattices 18 are arranged in a matrix and the central cross is removed.The third medium lattice 24 c is adjacent to one vertex of the firstmedium lattice 24 a and one side of the second medium lattice 24 b, andhas the same shape as the second medium lattice 24 b. The fourth mediumlattice 24 d is disposed at the intersection of the third side 32 c andthe first side 32 a, is adjacent to one vertex of the second mediumlattice 24 b and one side of the third medium lattice 24 c, and forms anL-shaped space in combination with one small lattice 18 as in the firstmedium lattice 24 a. When the small lattices 18 have an arrangementpitch of P, the medium lattices 24 have an arrangement pitch of 2P.

The above-described first dummy pattern 20A is formed around each of thefour sides 32 (the first side 32 a to the fourth side 32 d) of the firstlarge lattice 16A. The first dummy pattern 20A is such that a part ofthe small lattice 18 is removed to provide a remaining part, and two ormore remaining parts are arranged along the corresponding side (straightline). In the example of FIG. 1, the remaining part is provided byremoving one side from the small lattice 18 and thus has a shape withtwo corners and one opening (referred to simply as an approximately Ushape), and ten remaining parts are arranged such that the openings areopened in the direction away from the corresponding side of the firstlarge lattice 16A. The arrangement pitch of the remaining parts is twiceas large as the arrangement pitch P of the small lattices 18 in thefirst large lattice 16A. For example, the shortest distance between thestraight line shape of the first side 32 a and the approximately U shapeof the first dummy pattern 20A is approximately equal to the inside sidelength of the small lattice 18. This is true also for the second side 32b to the fourth side 32 d.

In the first insulation 28A, a first insulation pattern 34A unconnectedto the first large lattices 16A is formed. The first insulation pattern34A has a first assembly pattern portion 36 a containing two or moresmall lattices 18 arranged and three spaces 38 (38 a to 38 c) containingno small lattices 18.

Specifically, the first assembly pattern portion 36 a contains acombination of four straight lines (two long straight lines and twoshort straight lines) composed of a plurality of the small lattices 18.Each of the straight lines is formed by arranging a plurality of thesmall lattices 18 to connect the vertices of the small lattices 18. Withrespect to the adjacent two first large lattices 16A (and two secondlarge lattices 16B) with the first insulation 28A interposedtherebetween, the three spaces 38 include the first space 38 acontaining no small lattices 18 surrounded by the first assembly patternportion 36 a, the second space 38 b containing no small lattices 18formed around the other corner 30 b of one first large lattice 16A, andthe third space 38 c containing no small lattices 18 formed around theone corner 30 a of the other first large lattice 16A.

For example, among the four straight lines, each of the two longstraight lines is formed by arranging seven small lattices 18 to connectthe vertices thereof. The small lattice 18 in one end of one longstraight line is positioned adjacent to the first dummy pattern 20Aalong the third side 32 c of the one first large lattice 16A at the samepitch around the other corner 30 b of the one first large lattice 16A,and the small lattice 18 in the other end of the one long straight lineis positioned adjacent to the first dummy pattern 20A along the firstside 32 a of the other first large lattice 16A at the same pitch aroundthe one corner 30 a of the other first large lattice 16A. Similarly, thesmall lattice 18 in one end of the other long straight line ispositioned adjacent to the first dummy pattern 20A along the fourth side32 d of the one first large lattice 16A at the same pitch around theother corner 30 b of the one first large lattice 16A, and the smalllattice 18 in the other end of the other long straight line ispositioned adjacent to the first dummy pattern 20A along the second side32 b of the other first large lattice 16A at the same pitch around theone corner 30 a of the other first large lattice 16A.

Among the two short straight lines, one short straight line contains twosmall lattices 18 connecting the 2nd small lattice 18 from one end inthe one long straight line and the 2nd small lattice 18 from one end inthe other long straight line. Similarly, the other short straight linecontains two small lattices 18 connecting the 2nd small lattice 18 fromthe other end in the one long straight line and the 2nd small lattice 18from the other end in the other long straight line.

When the small lattices 18 have an arrangement pitch of P, the firstinsulation 28A has a width of m X P (in which m is an integer of 1 ormore). The width of the first insulation 28A is defined as the shortestdistance between the adjacent first conductive patterns 26A (i.e. thedistance between the other corner 30 b of the one first large lattice16A and the one corner 30 a of the other first large lattice 16A). Thus,the first insulation pattern 34A has a maximum length of m X P or lessin the width direction of the first insulation 28A. The maximum lengthis the distance between a part in the one short straight line facing theother corner 30 b of the one first large lattice 16A and a part in theother short straight line facing the one corner 30 a of the other firstlarge lattice 16A.

As described above, in the first conductive sheet 10A, the firstconductive pattern 26A composed of the thin metal wires 15 is formed byconnecting two or more first large lattices 16A in series in the firstdirection, the first large lattice 16A is formed by combining two ormore small lattices 18, the first dummy pattern 20A composed of the thinmetal wires 15 separated from the first large lattice 16A is formedaround each side of the first large lattice 16A, the thin metal wire 15has a line width of 1 to 15 μm, and the small lattice 18 has a sidelength of 50 to 500 μm. As a result, the first conductive sheet 10A canexhibit a significantly lowered electrical resistance as compared withconventional structures using one ITO film for one electrode. Thus, in acase where the first conductive sheet 10A is used in the projectedcapacitive touch panel 100 or the like, the response speed and the sizeof the touch panel 100 can be easily increased.

The touch panel 100 containing the above first conductive sheet 10A willbe described below with reference to FIGS. 3 to 22.

The touch panel 100 has a sensor body 102 and a control circuit such asan input circuit (not shown). As shown in FIGS. 3, 4, and 5A, the sensorbody 102 contains a touch panel conductive sheet according to the firstembodiment (hereinafter referred to as the first laminated conductivesheet 12A) and thereon a protective layer 106 (not shown in FIG. 5A).The first laminated conductive sheet 12A is obtained by stacking theabove first conductive sheet 10A and a second conductive sheet 10B to behereinafter described. The first laminated conductive sheet 12A and theprotective layer 106 are disposed on the display panel 110 of a displaydevice 108 such as a liquid crystal display. As viewed from above, thesensor body 102 has a sensing region 112 corresponding to a displayscreen 110 a of the display panel 110 and a terminal wiring region 114(a so-called frame) corresponding to the periphery of the display panel110.

In the first conductive sheet 10A of the touch panel 100, in one end ofeach first conductive pattern 26A, the first connection 22A is notformed on the open end of the first large lattice 16A. In the other endof the first conductive pattern 26A, the end of the first large lattice16A is electrically connected to a first terminal wiring pattern 42 acomposed of a thin metal wire 15 by a first wire connection 40 a (seeFIG. 4). As shown in FIG. 4, a plurality of the first conductivepatterns 26A are arranged in the sensing region 112, and a plurality ofthe first terminal wiring patterns 42 a extend from the first wireconnections 40 a in the terminal wiring region 114.

In the example of FIG. 3, the first conductive sheet 10A and the sensingregion 112 each have a rectangular shape as viewed from above. In theterminal wiring region 114, a plurality of first terminals 116 a arearranged in the length direction in the longitudinal center of theperiphery on one long side of the first conductive sheet 10A. The firstwire connections 40 a are arranged in a straight line in the y directionalong one long side of the sensing region 112 (a long side closest tothe one long side of the first conductive sheet 10A). The first terminalwiring pattern 42 a extends from each first wire connection 40 a to thecenter of the one long side of the first conductive sheet 10A, and iselectrically connected to the corresponding first terminal 116 a. Thus,the first terminal wiring patterns 42 a, connected to each pair ofcorresponding first wire connections 40 a formed on the right and leftof the one long side of the sensing region 112, have approximately thesame lengths. Of course, the first terminals 116 a may be formed in acorner of the first conductive sheet 10A or the vicinity thereof.However, in this case, the length difference between the longest andshortest first terminal wiring patterns 42 a is increased, whereby thelongest first terminal wiring pattern 42 a and the first terminal wiringpatterns 42 a in the vicinity thereof are disadvantageously poor in therate of transferring a signal to the corresponding first conductivepattern 26A. Thus, in this embodiment, the first terminals 116 a areformed in the longitudinal center of the one long side of the firstconductive sheet 10A, whereby the local signal transfer ratedeterioration is prevented to increase the response speed.

As shown in FIGS. 3, 4, and 5A, the second conductive sheet 10B has asecond conductive part 13B formed on one main surface of a secondtransparent substrate 14B (see FIG. 5A). The second conductive part 13Bcontains two or more conductive second large lattices 16B composed ofthin metal wires 15, and each of the second large lattices 16B containsa combination of two or more small lattices 18. A second dummy pattern20B (a second unconnected pattern) separated from the second largelattices 16B is formed around each side of the second large lattices16B. A second connection 22B composed of thin metal wires 15 is formedbetween each adjacent two of the second large lattices 16B toelectrically connect the second large lattices 16B. The secondconnection 22B contains one or more medium lattices 24 (24 e to 24 h),and the pitch of the medium lattices 24 is n times larger than that ofthe small lattices 18 (in which n is a real number larger than 1). Theside length of the second large lattice 16B is preferably 3 to 10 mm,more preferably 4 to 6 mm, as well as the first large lattice 16A.

Two or more of the second large lattices 16B are arranged in the ydirection (the second direction) with the second connections 22Bdisposed therebetween to form one second conductive pattern 26B, and twoor more of the second conductive patterns 26B are arranged in the xdirection (the first direction). Electrically isolated secondinsulations 28B are disposed between the adjacent second conductivepatterns 26B.

As shown in FIG. 4, for example, in one end of each alternate(odd-numbered, for example) second conductive pattern 26B and in theother end of each even-numbered second conductive pattern 26B, thesecond connection 22B is not formed on the open end of the second largelattice 16B. In the other end of each odd-numbered second conductivepattern 26B and in one end of each even-numbered second conductivepattern 26B, the end of the second large lattice 16B is electricallyconnected to a second terminal wiring pattern 42 b composed of a thinmetal wire 15 by a second wire connection 40 b.

A large number of the second conductive patterns 26B are arranged in thesensing region 112, and a plurality of the second terminal wiringpatterns 42 b extending from the second wire connections 40 b arearranged in the terminal wiring region 114.

As shown in FIG. 3, in the terminal wiring region 114, a plurality ofsecond terminals 116 b are arranged in the length direction in thelongitudinal center of the periphery on one long side of the secondconductive sheet 10B. For example, a plurality of (the odd-numbered)second wire connections 40 b are arranged in a straight line in the xdirection along one short side of the sensing region 112 (a short sideclosest to one short side of the second conductive sheet 10B), and aplurality of (the even-numbered) second wire connections 40 b arearranged in a straight line in the x direction along the other shortside of the sensing region 112 (a short side closest to the other shortside of the second conductive sheet 10B).

For example, among a plurality of the second conductive patterns 26B,each odd-numbered second conductive pattern 26B is connected to thecorresponding odd-numbered second wire connection 40 b, and eacheven-numbered second conductive pattern 26B is connected to thecorresponding even-numbered second wire connection 40 b. The secondterminal wiring patterns 42 b extend from the odd-numbered andeven-numbered second wire connections 40 b to the approximate center ofone long side of the second conductive sheet 10B, and are eachelectrically connected to the corresponding second terminal 116 b. Thus,for example, the 1st and 2nd second terminal wiring patterns 42 b haveapproximately the same lengths, and similarly the (2n−1)-th and (2n)-thsecond terminal wiring patterns 42 b have approximately the same lengths(n=1, 2, 3, . . . ).

Of course, the second terminals 116 b may be formed in a corner of thesecond conductive sheet 10B or the vicinity thereof. However, in thiscase, as described above, the longest second terminal wiring pattern 42b and the second terminal wiring patterns 42 b in the vicinity thereofare disadvantageously poor in the rate of transferring a signal to thecorresponding second conductive pattern 26B. Thus, in this embodiment,the second terminals 116 b are formed in the longitudinal center of theone long side of the second conductive sheet 10B, whereby the localsignal transfer rate deterioration is prevented so that the responsespeed is increased.

The first terminal wiring patterns 42 a may be arranged in the samemanner as in the above second terminal wiring patterns 42 b, and thesecond terminal wiring patterns 42 b may be arranged in the same manneras in the above first terminal wiring patterns 42 a.

In a case where the first laminated conductive sheet 12A is used in atouch panel, the protective layer 106 is formed on the first conductivesheet 10A, and the first terminal wiring patterns 42 a extending from alarge number of the first conductive patterns 26A in the firstconductive sheet 10A and the second terminal wiring patterns 42 bextending from a large number of the second conductive patterns 26B inthe second conductive sheet 10B are connected to a scan control circuitor the like.

A self or mutual capacitance technology can be preferably used fordetecting a touch position. In the self capacitance technology, avoltage signal for the touch position detection is sequentially suppliedto the first conductive patterns 26A, and further a voltage signal forthe touch position detection is sequentially supplied to the secondconductive patterns 26B. When a finger is brought into contact with orclose to the upper surface of the protective layer 106, the capacitancebetween the first conductive pattern 26A and the second conductivepattern 26B corresponding to the touch position (the position in theupper surface of the protective layer 106 which the finger is broughtinto contact with or close to), and the GND (ground) is increased,whereby signals from this first conductive pattern 26A and this secondconductive pattern 26B have a waveform different from those of signalsfrom the other conductive patterns. Thus, the touch position iscalculated by the control circuit based on the signals transmitted fromthe first conductive pattern 26A and the second conductive pattern 26B.On the other hand, in the mutual capacitance technology, for example, avoltage signal for the touch position detection is sequentially suppliedto the first conductive patterns 26A, and the second conductive patterns26B are sequentially subjected to a sensing process (transmitted signaldetection). When a finger is brought into contact with or close to theupper surface of the protective layer 106, the parallel straycapacitance of the finger is added to the parasitic capacitance betweenthe first conductive pattern 26A and the second conductive pattern 26Bcorresponding to the touch position, whereby a signal from this secondconductive pattern 26B has a waveform different from those of signalsfrom the other second conductive patterns 26B. Thus, the touch positionis calculated by the control circuit based on the order of the firstconductive patterns 26A supplied with the voltage signal and the signaltransmitted from the second conductive pattern 26B. Even when twofingers are brought into contact with or close to the upper surface ofthe protective layer 106 simultaneously, the touch positions can bedetected by using the self or mutual capacitance technology.Conventional related detection circuits used in projected capacitivetechnologies are described in U.S. Pat. Nos. 4,582,955, 4,686,332,4,733,222, 5,374,787, 5,543,588, and 7,030,860, US Patent PublicationNo. 2004/0155871, etc.

As shown in FIG. 6, the second large lattice 16B has an approximatelyoctagonal shape unlike the first large lattice 16A. The second largelattice 16B has four short sides 44 (a first short side 44 a to a fourthshort side 44 d) and four long sides 46 (a first long side 46 a to afourth long side 46 d). With respect to the second large lattices 16Barranged adjacent in the y direction, the second connection 22B isformed between the first short side 44 a of one second large lattice 16Band the second short side 44 b of another second large lattice 16B. Withrespect to the second large lattices 16B arranged adjacent in the xdirection, the second insulation 28B is formed between the third shortside 44 c of one second large lattice 16B and the fourth short side 44 dof another second large lattice 16B.

The four long sides of the second large lattice 16B each have a straightline shape, i.e., the first long side 46 a and the second long side 46 badjacent to the third short side 44 c facing one second insulation 28B,and the third long side 46 c and the fourth long side 46 d are adjacentto the fourth short side 44 d facing another second insulation 28B.

In the second connection 22B, the four medium lattices 24 (the fifthmedium lattice 24 e to the eighth medium lattice 24 h) are arranged in azigzag manner, and each of the medium lattices 24 has a size equal tothe total of four small lattices 18. The fifth medium lattice 24 e isdisposed on the first short side 44 a, and forms an L-shaped space incombination with one small lattice 18. The sixth medium lattice 24 f isdisposed on one side of the fifth medium lattice 24 e, and forms such asquare space that four small lattices 18 are arranged in a matrix andthe central cross is removed. The seventh medium lattice 24 g isadjacent to one vertex of the fifth medium lattice 24 e and one side ofthe sixth medium lattice 24 f, and has the same shape as the sixthmedium lattice 24 f. The eighth medium lattice 24 h is disposed on thesecond short side 44 b, is adjacent to one vertex of the sixth mediumlattice 24 f and one side of the seventh medium lattice 24 g, and formsan L-shaped space in combination with one small lattice 18 as in thefifth medium lattice 24 e. When the small lattices 18 have anarrangement pitch of P, the medium lattices 24 have an arrangement pitchof 2P.

The above-described second dummy pattern 20B is formed around each ofthe four long sides 46 (the first long side 46 a to the fourth long side46 d) of the second large lattice 16B. The second dummy pattern 20B isprovided such that a part of the small lattice 18 is removed to providea remaining part, and two or more remaining parts are arranged along thecorresponding side (straight line shape). In the example of FIG. 6, theremaining part is provided by removing one side from the small lattice18 and thus has an approximately U shape, and ten remaining parts arearranged such that the openings are opened in the direction away fromthe corresponding long side of the second large lattice 16B. Thearrangement pitch of the remaining parts is twice as large as thearrangement pitch P of the small lattices 18 in the second largelattices 16B. For example, the shortest distance between the straightline shape of the first long side 46 a and the approximately U shape ofthe second dummy pattern 20B is approximately equal to the inside sidelength of the small lattice 18. This is true also for the second longside 46 b to the fourth long side 46 d.

In the second insulation 28B, a second insulation pattern 34Bunconnected to the second large lattices 16B is formed. The secondinsulation pattern 34B has a second assembly pattern portion 36 bcontaining two or more small lattices 18 arranged, a first bend patternportion 48 a and a second bend pattern portion 48 b each containing twoapproximately U shapes, and one space (a fourth space 38 d) containingno small lattices 18.

Specifically, the second assembly pattern portion 36 b is formed byarranging a plurality of (for example six) small lattices 18 in a matrixto connect the vertices of the small lattices 18. The number of thesmall lattices 18 is determined such that the small lattices 18 can beplaced in the first space 38 a of the first insulation pattern 34A inthe first conductive pattern 26A shown in FIG. 1.

The first bend pattern portion 48 a has the two approximately U shapesformed on one end of the second insulation pattern 34B (between theintersection of the fourth short side 44 d and the third long side 46 cin one second large lattice 16B and the intersection of the third shortside 44 c and the first long side 46 a in another second large lattice16B). The ends of the two approximately U shapes are connected, and anangle formed by the sides at the ends is approximately 90°.

Similarly, the second bend pattern portion 48 b has the twoapproximately U shapes formed on the other end of the second insulationpattern 34B (between the intersection of the fourth short side 44 d andthe fourth long side 46 d in the one second large lattice 16B and theintersection of the third short side 44 c and the second long side 46 bin the other second large lattice 16B). The ends of the twoapproximately U shapes are connected, and an angle formed by the sidesat the ends is approximately 90°.

The fourth space 38 d (containing no small lattices 18) has a shape inwhich the four straight lines of the first assembly pattern portion 36 ain the first insulation pattern 34A shown in FIG. 1 can be placed.

When the small lattices 18 have an arrangement pitch P, the secondinsulation 28B has a width of n×P (in which n is an integer of 1 ormore). The width of the second insulation 28B is defined as the shortestdistance between the adjacent second conductive patterns 26B (i.e. thedistance between the fourth short side 44 d of the one second largelattice 16B and the third short side 44 c of the other second largelattice 16B). Thus, the second insulation pattern 34B has a maximumlength of n×P or less, preferably less than n×P, in the width directionof the second insulation 28B. The maximum length is the distance betweena part facing the fourth short side 44 d of the one second large lattice16B and a part facing the third short side 44 c of the other secondlarge lattice 16B in the second assembly pattern portion 36 b.

For example, as shown in FIG. 7, in a case where the first conductivesheet 10A is stacked on the second conductive sheet 10B to form thefirst laminated conductive sheet 12A, the first connections 22A of thefirst conductive patterns 26A and the second connections 22B of thesecond conductive patterns 26B are arranged facing each other with thefirst transparent substrate 14A (see FIG. 5A) interposed therebetween,and the first insulations 28A of the first conductive patterns 26A andthe second insulations 28B of the second conductive patterns 26B arearranged facing each other with the first transparent substrate 14Ainterposed therebetween. Though the first conductive patterns 26A andthe second conductive patterns 26B have the same line width, they areexaggeratingly shown by thick lines and thin lines respectively toclearly represent the positions thereof in FIG. 7.

When the stack of the first conductive sheet 10A and the secondconductive sheet 10B is viewed from above, spaces between the firstlarge lattices 16A in the first conductive sheet 10A are filled with thesecond large lattices 16B in the second conductive sheet 10B. Thus, thesensing region 112 is covered with the large lattices. In this case, thefirst dummy patterns 20A and the second dummy patterns 20B overlap witheach other to form combined patterns between the first large lattices16A and the second large lattices 16B. The combined pattern has a widthequal to or larger than the side length of the small lattice 18. Thewidth of the combined pattern is defined as the shortest distanceprojected on one main surface of the first transparent substrate 14A forexample between the first side 32 a of the first large lattice 16A andthe second long side 46 b (facing the first side 32 a) of the secondlarge lattice 16B. In the example of FIG. 7, the width of the combinedpattern is twice as large as the side length of the small lattice 18.This is true also for the relations between the second side 32 b to thefourth side 32 d of the first large lattice 16A and the second long side46 b to the fourth long side 46 d of the second large lattice 16B.

Thus, as viewed from above, the openings of the approximately U shapesin the first dummy patterns 20A along the first large lattices 16A areclosed by the straight long sides of the second large lattices 16B, andthe bottoms of the approximately U shapes in the first dummy patterns20A are connected by the bottoms of the approximately U shapes in thesecond dummy patterns 20B along the second large lattices 16B.Similarly, the openings of the approximately U shapes in the seconddummy patterns 20B along the second large lattices 16B are closed by thestraight long sides of the first large lattices 16A, and the bottoms ofthe approximately U shapes in the second dummy patterns 20B areconnected by the bottoms of the approximately U shapes in the firstdummy patterns 20A along the first large lattices 16A. As a result, aplurality of the small lattices 18 are arranged as viewed from above,and the boundaries between the first large lattices 16A and the secondlarge lattices 16B can hardly be found.

For example, in the case of not forming the first dummy patterns 20A andthe second dummy patterns 20B, blank areas corresponding to the combinedpattern width are formed, whereby the edges of the first large lattices16A and the second large lattices 16B are highly visible, and thevisibility is deteriorated. This problem may be solved by overlappingeach side of the first large lattices 16A with the corresponding longside of the second large lattices 16B to prevent the formation of theblank area. However, when the stack position accuracy is slightlydeteriorated, the overlaps of the straight lines have increased widths(the overlaps are thickened), whereby the boundaries between the firstlarge lattices 16A and the second large lattices 16B are highly visible,and thus the visibility is again deteriorated.

In contrast, in this embodiment, the first dummy patterns 20A and thesecond dummy patterns 20B are stacked in the above manner, whereby theboundaries between the first large lattices 16A and the second largelattices 16B are made less visible to improve the visibility.

In the case of overlapping each side of the first large lattices 16Awith the corresponding long side of the second large lattices 16B toprevent the formation of the blank area as described above, the first tofourth long sides 46 a to 46 d of the second large lattices 16B arepositioned right under the first to fourth sides 32 a to 32 d of thefirst large lattice 16A. In this case, all the first to fourth sides 32a to 32 d and the first to fourth long sides 46 a to 46 d function asconductive portions, so that a parasitic capacitance is formed betweenthe side of the first large lattice 16A and the long side of the secondlarge lattice 16B, and the parasitic capacitance acts as a noise oncharge information, causing significant deterioration in the S/N ratio.Furthermore, since the parasitic capacitance is formed between each pairof the first large lattice 16A and the second large lattice 16B, a largenumber of the parasitic capacitances are connected in parallel in thefirst conductive patterns 26A and the second conductive patterns 26B,resulting in increase of the CR time constant. When the CR time constantis increased, there is a possibility that the waveform rise of thevoltage signal supplied to the first conductive pattern 26A (and thesecond conductive pattern 26B) is retarded, and an electric field forthe position detection is hardly generated under a predetermined scantime. In addition, there is also a possibility that the waveform rise orfall of the signal transmitted from each of the first conductivepatterns 26A and the second conductive patterns 26B is retarded, and thewaveform change of the transmitted signal cannot be detected under apredetermined scan time. This leads to detection accuracy deteriorationand response speed deterioration. Thus, in this case, the detectionaccuracy and response speed can be improved only by reducing the numberof the first large lattices 16A and the second large lattices 16B(lowering the resolution) or by reducing the size of the display screen,and the laminated conductive sheet cannot be used in a large screen suchas a B5 sized, A4 sized, or larger screen.

In contrast, in this embodiment, as shown in FIG. 5A, the projecteddistance Lf between the side 32 of the first large lattice 16A and thelong side 46 of the second large lattice 16B is approximately twice aslarge as the side length of the small lattice 18. Therefore, only asmall parasitic capacitance is formed between the first large lattice16A and the second large lattice 16B. As a result, the CR time constantcan be reduced to improve the detection accuracy and the response speed.In the combined pattern of the first dummy pattern 20A and the seconddummy pattern 20B, each corner of the first dummy pattern 20A overlapswith the corresponding corner of the second dummy pattern 20B. However,this overlap does not result in increase of the parasitic capacitancebetween the first large lattice 16A and the second large lattice 16Bbecause the first dummy pattern 20A is unconnected with and electricallyisolated from the first large lattice 16A and the second dummy pattern20B is unconnected with and electrically isolated from the second largelattice 16B.

It is preferred that the optimum value of the projected distance Lf isappropriately determined depending not on the sizes of the first largelattices 16A and the second large lattices 16B but on the sizes (theline widths and the side lengths) of the small lattices 18 in the firstlarge lattices 16A and the second large lattices 16B. When the smalllattices 18 have an excessively large size as compared with the sizes ofthe first large lattices 16A and the second large lattices 16B, theresultant conductive sheet may have a high light transmittance, but thedynamic range of the transmitted signal may be reduced, lowering thedetection sensitivity. On the other hand, when the small lattices 18have an excessively small size, the resultant conductive sheet may havehigh detection sensitivity, but the light transmittance may bedeteriorated under the restriction of line width reduction.

When the small lattices 18 have a line width of 1 to 9 μm, the optimumvalue of the projected distance Lf (the optimum distance) is preferably100 to 400 μm, more preferably 200 to 300 μm. In a case where the smalllattices 18 have a smaller line width, the optimum distance can befurther reduced. However, in this case, the electrical resistance isincreased, so that the CR time constant may be increased even under asmall parasitic capacitance, disadvantageously deteriorating thedetection sensitivity and the response speed. Thus, the line width ofthe small lattice 18 is preferably within the above range.

For example, the sizes of the first large lattice 16A, the second largelattice 16B, and the small lattice 18 are determined based on the sizeof the display panel 110 or the size and touch position detectionresolution (drive pulse period or the like) of the sensing region 112,and the optimum distance between the first large lattice 16A and thesecond large lattice 16B is obtained based on the line width of thesmall lattice 18.

When the overlap of the first connection 22A and the second connection22B is viewed from above, the connection point of the fifth mediumlattice 24 e and the seventh medium lattice 24 g in the secondconnection 22B is positioned approximately at the center of the secondmedium lattice 24 b around the first large lattice 16A, the connectionpoint of the sixth medium lattice 24 f and the eighth medium lattice 24h in the second connection 22B is positioned approximately at the centerof the third medium lattice 24 c around the first large lattice 16A, andthe first medium lattice 24 a to the eighth medium lattice 24 h form aplurality of the small lattices 18 in combination. Therefore, the smalllattices 18 are formed by the combination of the first connections 22Aand the second connections 22B in the overlaps thereof. Thus formedsmall lattices 18 cannot be distinguished from the surrounding smalllattices 18 in the first large lattices 16A and the second largelattices 16B, so that the visibility is improved.

When the overlap of the first insulation pattern 34A of the firstinsulation 28A and the second insulation pattern 34B of the secondinsulation 28B is viewed from above, the first assembly pattern portion36 a of the first insulation pattern 34A is arranged facing the fourthspace 38 d of the second insulation pattern 34B, and the first space 38a of the first insulation pattern 34A is arranged facing the secondassembly pattern portion 36 b of the second insulation pattern 34B.Furthermore, the second space 38 b of the first insulation pattern 34Ais arranged facing the first bend pattern portion 48 a of the secondinsulation pattern 34B, and the third space 38 c of the first insulationpattern 34A is arranged facing the second bend pattern portion 48 b ofthe second insulation pattern 34B. In this case, as viewed from above,the opening of the first bend pattern portion 48 a is closed by thestraight line shapes of the third side 32 c and the fourth side 32 daround the other corner 30 b of the first large lattice 16A, and theopening of the second bend pattern portion 48 b is closed by thestraight line shapes of the first side 32 a and the second side 32 baround the one corner 30 a of the first large lattice 16A. Therefore,the first insulation patterns 34A and the second insulation patterns 34Bform a plurality of the small lattices 18 in combination. Thus formedsmall lattices 18 cannot be distinguished from the surrounding smalllattices 18 in the first large lattices 16A and the second largelattices 16B, so that the visibility is improved.

In this embodiment, in the terminal wiring region 114, a plurality ofthe first terminals 116 a are formed in the longitudinal center of theperiphery on the one long side of the first conductive sheet 10A, and aplurality of the second terminals 116 b are formed in the longitudinalcenter of the periphery on the one long side of the second conductivesheet 10B. Particularly, in the example of FIG. 3, the first terminals116 a and the second terminals 116 b do not overlap with each other butare close to each other, and the first terminal wiring patterns 42 a andthe second terminal wiring patterns 42 b do not overlap with each other.For example, the first terminal 116 a may partially overlap with theodd-numbered second terminal wiring pattern 42 b.

Thus, the first terminals 116 a and the second terminals 116 b can beelectrically connected to the control circuit by using a cable and twoconnectors (a connector for the first terminals 116 a and a connectorfor the second terminals 116 b) or one connector (a complex connector tobe connected to the first terminals 116 a and the second terminals 116b).

Since the first terminal wiring patterns 42 a and the second terminalwiring patterns 42 b do not vertically overlap with each other, aparasitic capacitance generation is reduced therebetween so that theresponse speed deterioration is prevented.

Since the first wire connections 40 a are arranged along the one longside of the sensing region 112 and the second wire connections 40 b arearranged along both the short sides of the sensing region 112, the areaof the terminal wiring region 114 can be reduced. Therefore, the size ofthe display panel 110 containing the touch panel 100 can be easilyreduced, and the display screen 110 a can be made to seem larger. Alsothe operability of the touch panel 100 can be improved.

The area of the terminal wiring region 114 may be further reduced byreducing the distance between the adjacent first terminal wiringpatterns 42 a or the adjacent second terminal wiring patterns 42 b. Thedistance is preferably 10 to 50 μm in view of preventing migration.

Alternatively, the area of the terminal wiring region 114 may be reducedby arranging the second terminal wiring pattern 42 b between theadjacent first terminal wiring patterns 42 a as viewed from above.However, when the pattern is misaligned, the first terminal wiringpattern 42 a may vertically overlap with the second terminal wiringpattern 42 b, so that the parasitic capacitance therebetween becomesdisadvantageously increased. This leads to the response speeddeterioration. Thus, in the case of using such an arrangement, thedistance between the adjacent first terminal wiring patterns 42 a ispreferably 50 to 100 μm.

Consequently, when the first laminated conductive sheet 12A is used inthe projected capacitive touch panel 100 or the like, the response speedand the size of the touch panel 100 can be easily increased.

The combination of the first dummy patterns 20A formed around the firstlarge lattices 16A in the first conductive sheet 10A and the seconddummy patterns 20B formed around the second large lattices 16B in thesecond conductive sheet 10B, the combination of the first connections22A and the second connections 22B, and the combination of the firstinsulation patterns 34A and the second insulation patterns 34B form aplurality of the small lattices 18. Therefore, the boundaries betweenthe first large lattices 16A of the first conductive sheet 10A and thesecond large lattices 16B of the second conductive sheet 10B can be madeless visible, defects such as the local line thickening can beprevented, and the overall visibility can be improved.

Furthermore, the CR time constant of a large number of the firstconductive patterns 26A and the second conductive patterns 26B can besignificantly reduced, whereby the response speed can be increased, andthe position detection can be readily carried out in an operation time(a scan time). Thus, the screen sizes (not the thickness but the lengthand width) of the touch panel 100 can be easily increased.

Though the first large lattice 16A has a rectangular outer shape asshown in FIG. 1 and the second large lattice 16B has an octagonal outershape as shown in FIG. 6 in the above example, the outer shapes of thefirst large lattice 16A and the second large lattice 16B are not limitedthereto. Also the sizes of the first large lattice 16A and the secondlarge lattice 16B are not particularly limited as long as the sizes aresufficient for detecting the touch position.

Though the small lattice 18 has a square shape in the above example, itmay have another polygonal shape. Each side of the small lattice 18 mayhave a straight line shape, a curved shape, or an arc shape. When thesmall lattice 18 has an arc-shaped side, for example, two opposite sidesmay have an outwardly protruding arc shape and the other two oppositesides may have an inwardly protruding arc shape. Alternatively, eachside may have a wavy shape containing outwardly protruding arcs andinwardly protruding arcs continuously. Of course, each side may have asine curve shape.

Though the arrangement pitch of the medium lattices 24 in the firstconnections 22A and the second connections 22B is twice larger than thearrangement pitch P of the small lattices 18 in the above firstconductive sheet 10A and second conductive sheet 10B, it may beappropriately selected depending on the number of the medium lattices24. For example, the arrangement pitch of the medium lattices 24 may be1.5 or 3 times larger than the arrangement pitch P of the small lattices18. When the arrangement pitch of the medium lattices 24 is excessivelysmall or large, it may be difficult to arrange the first large lattices16A and the second large lattices 16B, resulting in poor appearance.Thus, the arrangement pitch of the medium lattices 24 is preferably 1 to10 times, more preferably 1 to 5 times, larger than the arrangementpitch P of the small lattices 18.

Also the sizes of the small lattices 18 (including the side length andthe diagonal line length), the number of the small lattices 18 in thefirst large lattice 16A, and the number of the small lattices 18 in thesecond large lattice 16B may be appropriately selected depending on thesize and the resolution (the number of wires) of the touch panel.

As shown in FIGS. 3, 4, and 5A, in the above first laminated conductivesheet 12A, the first conductive patterns 26A are formed on one mainsurface of the first transparent substrate 14A, and the secondconductive patterns 26B are formed on one main surface of the secondtransparent substrate 14B. Alternatively, as shown in FIG. 5B, the firstconductive part 13A may be formed on one main surface of the firsttransparent substrate 14A, and the second conductive part 13B may beformed on the other main surface of the first transparent substrate 14A.In this case, the second transparent substrate 14B is not used, thefirst transparent substrate 14A is stacked on the second conductive part13B, and the first conductive part 13A is stacked on the firsttransparent substrate 14A. In addition, another layer may be disposedbetween the first conductive sheet 10A and the second conductive sheet10B. The first conductive patterns 26A and the second conductivepatterns 26B may be arranged facing each other as long as they areinsulated.

Three structures shown schematically in FIGS. 8A to 8C can be preferablyused in this embodiment.

In a first structure example shown in FIG. 8A, the first laminatedconductive sheet 12A shown in FIG. 5B (containing the first conductivepart 13A, the first transparent substrate 14A, and the second conductivepart 13B) is stacked on the display device 108 with a transparentadhesive 120 interposed therebetween, a hard coat layer 122 is stackedon the first laminated conductive sheet 12A, and further anantireflection layer 124 is stacked on the hard coat layer 122. Thetransparent adhesive 120, the second conductive part 13B, the firsttransparent substrate 14A, and the first conductive part 13A form thetouch panel 100 on the display device 108, and the hard coat layer 122and the antireflection layer 124 form an antireflection film 126 on thetouch panel 100.

In a second structure example shown in FIG. 8B, the first laminatedconductive sheet 12A shown in FIG. 5B and a protective resin layer 128are stacked on the display device 108 with the transparent adhesive 120interposed therebetween, the hard coat layer 122 is stacked on theprotective resin layer 128, and further the antireflection layer 124 isstacked on the hard coat layer 122. The transparent adhesive 120, thesecond conductive part 13B, the first transparent substrate 14A, thefirst conductive part 13A, and the protective resin layer 128 form thetouch panel 100 on the display device 108, and the hard coat layer 122and the antireflection layer 124 form the antireflection film 126 on thetouch panel 100.

In a third structure example shown in FIG. 8C, the first laminatedconductive sheet 12A shown in FIG. 5B and a second transparent adhesive120B are stacked on the display device 108 with a first transparentadhesive 120A interposed therebetween, a transparent film 130 is stackedon the second transparent adhesive 120B, the hard coat layer 122 isstacked on the transparent film 130, and further the antireflectionlayer 124 is stacked on the hard coat layer 122. The first transparentadhesive 120A, the second conductive part 13B, the first transparentsubstrate 14A, the first conductive part 13A, and the second transparentadhesive 120B form the touch panel 100 on the display device 108, andthe transparent film 130, the hard coat layer 122, and theantireflection layer 124 form the antireflection film 126 on the touchpanel 100.

As shown in FIG. 3, first alignment marks 118 a and second alignmentmarks 118 b are preferably formed, for example on the corners of thefirst conductive sheet 10A and the second conductive sheet 10B. Thefirst alignment marks 118 a and the second alignment marks 118 b areused for positioning the first conductive sheet 10A and the secondconductive sheet 10B in a bonding process. In a case where the firstconductive sheet 10A and the second conductive sheet 10B are bonded toobtain the first laminated conductive sheet 12A, composite alignmentmarks are formed by the first alignment marks 118 a and the secondalignment marks 118 b. The composite alignment marks can be used forpositioning the first laminated conductive sheet 12A in the process ofattaching to the display panel 110.

A touch panel conductive sheet according to a second embodiment(hereinafter referred to as the second laminated conductive sheet 12B)will be described below with reference to FIGS. 9 to 12.

As shown in FIG. 9, the second laminated conductive sheet 12B hasapproximately the same structure as the above first laminated conductivesheet 12A, but is different in the shapes of the first insulationpattern 34A in the first insulation 28A and the second insulationpattern 34B in the second insulation 28B.

As shown in FIG. 10, the shape of the first assembly pattern portion 36a in the first insulation pattern 34A is such that the first space 38 a(see FIG. 1) is filled with the second assembly pattern portion 36 b(see FIG. 6). Thus, the first assembly pattern portion 36 a is filledwith the small lattices 18 between the opposite short straight lines,and the first insulation pattern 34A does not have the first space 38 a.As shown in FIG. 11, the shape of the fourth space 38 d in the secondinsulation pattern 34B is such that the second assembly pattern portion36 b (see FIG. 6) is removed. Thus, the second insulation 28B has nosmall lattices 18.

For example, as shown in FIG. 12, in a case where the first conductivesheet 10A is stacked on the second conductive sheet 10B to form thesecond laminated conductive sheet 12B, as in the first laminatedconductive sheet 12A (see FIG. 7), the first connections 22A of thefirst conductive patterns 26A and the second connections 22B of thesecond conductive patterns 26B are arranged facing each other with thefirst transparent substrate 14A (see FIG. 5A) interposed therebetween,and the first insulations 28A of the first conductive patterns 26A andthe second insulations 28B of the second conductive patterns 26B arearranged facing each other with the first transparent substrate 14Ainterposed therebetween. Though the first conductive patterns 26A andthe second conductive patterns 26B have the same line width, they areexaggeratingly shown by thick lines and thin lines respectively toclearly represent the positions thereof in FIG. 12 as well as FIG. 7.

Particularly, when the overlap of the first insulation pattern 34A ofthe first insulation 28A and the second insulation pattern 34B of thesecond insulation 28B is viewed from above, the first assembly patternportion 36 a of the first insulation pattern 34A is arranged facing thefourth space 38 d of the second insulation pattern 34B, the second space38 b of the first insulation pattern 34A is arranged facing the firstbend pattern portion 48 a of the second insulation pattern 34B, and thethird space 38 c of the first insulation pattern 34A is arranged facingthe second bend pattern portion 48 b of the second insulation pattern34B. Consequently, as in the first laminated conductive sheet 12A, thefirst insulation patterns 34A and the second insulation patterns 34Bform a plurality of the small lattices 18 in combination. Thus formedsmall lattices 18 cannot be distinguished from the surrounding smalllattices 18 in the first large lattices 16A and the second largelattices 16B, so that the visibility is improved.

Though not shown in the drawings, the arrangement of the first wireconnections 40 a and the second wire connections 40 b, the arrangementof the first terminal wiring patterns 42 a and the second terminalwiring patterns 42 b in the terminal wiring region 114, and thearrangement of the first terminals 116 a and the second terminals 116 bin the second laminated conductive sheet 12B are equal to those in theabove first laminated conductive sheet 12A.

Consequently, when the second laminated conductive sheet 12B using thesecond conductive sheet 10B is used in the projected capacitive touchpanel 100 or the like, the response speed and the size of the touchpanel 100 can be easily increased. Furthermore, the boundaries betweenthe first large lattices 16A of the first conductive sheet 10A and thesecond large lattices 16B of the second conductive sheet 10B can be madeless visible, defects such as the local line thickening can beprevented, and the overall visibility can be improved.

A touch panel conductive sheet according to a third embodiment(hereinafter referred to as the third laminated conductive sheet 12C)will be described below with reference to FIGS. 13 to 16.

As shown in FIG. 13, the third laminated conductive sheet 12C hasapproximately the same structure as the above first laminated conductivesheet 12A, but is different in the shapes of the first insulationpattern 34A in the first insulation 28A and the second insulationpattern 34B in the second insulation 28B.

As shown in FIG. 14, in the first insulation pattern 34A, four wavylines 50 (a first wavy line 50 a to a fourth wavy line 50 d) extendingin the y direction are arranged in parallel. Each of the four wavy lines50 has such a structure that two sides of the small lattice 18 arecontinuously arranged. Among the four wavy lines 50, the ends of theouter first wavy line 50 a and the outer second wavy line 50 b areconnected to the small lattices 18, and the ends of the inner third wavyline 50 c and the inner fourth wavy line 50 d are not connected to thesmall lattices 18. The positions of the small lattices 18 at the ends ofthe first wavy line 50 a and the second wavy line 50 b are equal tothose at the ends of the long straight lines of the first insulationpattern 34A in the first laminated conductive sheet 12A (see FIG. 1).

The adjacent first and third wavy lines 50 a and 50 c have the same waveshape (pattern), and the adjacent second and fourth wavy lines 50 b and50 d have the same wave shape (pattern). The outer first wavy line 50 ahas a wave shape (pattern) opposite to that of the outer second wavyline 50 b, and the inner third wavy line 50 c has a wave shape (pattern)opposite to that of the inner fourth wavy line 50 d.

In the first insulation pattern 34A, a first space 38 a is formedbetween the adjacent third and fourth wavy lines 50 c and 50 d, a secondspace 38 b is formed between the adjacent first and third wavy lines 50a and 50 c, and a third space 38 c is formed between the adjacent secondand fourth wavy lines 50 b and 50 d.

On the other hand, as shown in FIG. 15, the second insulation pattern34B has a first assembly pattern portion 36 a to be placed in the firstspace 38 a of the first insulation pattern 34A, a fifth wavy line 50 eto be placed in the second space 38 b of the first insulation pattern34A, and a sixth wavy line 50 f to be placed in the third space 38 c ofthe first insulation pattern 34A. The first assembly pattern portion 36a is connected to the first bend pattern portion 48 a and the secondbend pattern portion 48 b, and is formed by arranging two or more smalllattices 18 (for example six small lattices 18) to connect the verticesthereof.

The fifth wavy line 50 e in the second insulation pattern 34B has a waveshape (pattern) opposite to those of the first and third wavy lines 50 aand 50 c in the first insulation pattern 34A. Similarly, the sixth wavyline 50 f in the second insulation pattern 34B has a wave shape(pattern) opposite to those of the second and fourth wavy lines 50 b and50 d in the first insulation pattern 34A.

For example, as shown in FIG. 16, in a case where the first conductivesheet 10A is stacked on the second conductive sheet 10B to form thethird laminated conductive sheet 12C, as in the first laminatedconductive sheet 12A (see FIG. 7), the first connections 22A of thefirst conductive patterns 26A and the second connections 22B of thesecond conductive patterns 26B are arranged facing each other with thefirst transparent substrate 14A (see FIG. 5A) interposed therebetween,and the first insulations 28A of the first conductive patterns 26A andthe second insulations 28B of the second conductive patterns 26B arearranged facing each other with the first transparent substrate 14Ainterposed therebetween. Though the first conductive patterns 26A andthe second conductive patterns 26B have the same line width, they areexaggeratingly shown by thick lines and thin lines respectively toclearly represent the positions thereof in FIG. 16 as well as FIG. 7.

Particularly, when the overlap of the first insulation pattern 34A ofthe first insulation 28A and the second insulation pattern 34B of thesecond insulation 28B is viewed from above, the first space 38 a of thefirst insulation pattern 34A is arranged facing the first assemblypattern portion 36 a of the second insulation pattern 34B, the secondspace 38 b of the first insulation pattern 34A is arranged facing thefifth wavy line 50 e of the second insulation pattern 34B, and the thirdspace 38 c of the first insulation pattern 34A is arranged facing thesixth wavy line 50 f of the second insulation pattern 34B. Consequently,as in the first laminated conductive sheet 12A, the first insulationpatterns 34A and the second insulation patterns 34B form a plurality ofthe small lattices 18 in combination. Thus formed small lattices 18cannot be distinguished from the surrounding small lattices 18 in thefirst large lattices 16A and the second large lattices 16B, so that thevisibility is improved.

Though not shown in the drawings, the arrangement of the first wireconnections 40 a and the second wire connections 40 b, the arrangementof the first terminal wiring patterns 42 a and the second terminalwiring patterns 42 b in the terminal wiring region 114, and thearrangement of the first terminals 116 a and the second terminals 116 bin the third laminated conductive sheet 12C are equal to those in theabove first laminated conductive sheet 12A.

Consequently, when the third laminated conductive sheet 12C is used inthe projected capacitive touch panel 100 or the like, the response speedand the size of the touch panel 100 can be easily increased.Furthermore, the boundaries between the first large lattices 16A of thefirst conductive sheet 10A and the second large lattices 16B of thesecond conductive sheet 10B can be made less visible, defects such asthe local line thickening can be prevented, and the overall visibilitycan be improved.

A touch panel conductive sheet according to a fourth embodiment(hereinafter referred to as the fourth laminated conductive sheet 12D)will be described below with reference to FIGS. 17 to 22.

As shown in FIGS. 17 and 18A, the first conductive sheet 10A is stackedon the second conductive sheet 10B in the fourth laminated conductivesheet 12D as in the first laminated conductive sheet 12A and the like.The first conductive sheet 10A has the first conductive part 13A formedon one main surface of the first transparent substrate 14A, and thesecond conductive sheet 10B has the second conductive part 13B formed onone main surface of the second transparent substrate 14B.

As shown in FIGS. 17 and 19, the first conductive part 13A contains twoor more first conductive patterns 26A and first dummy patterns 20A. Thefirst conductive patterns 26A extend in the first direction (the xdirection), are arranged in the second direction (the y direction)perpendicular to the first direction, and each contain a large number oflattices. The first dummy patterns 20A are arranged around the firstconductive patterns 26A.

The first conductive pattern 26A contains two or more first largelattices 16A connected in series in the first direction. The first largelattices 16A each contain a combination of two or more small lattices18. The above first dummy pattern 20A is formed around each side 32 ofthe first large lattice 16A and is not connected to the first largelattice 16A.

A first connection 22A is formed between each adjacent two of the firstlarge lattices 16A to electrically connect the first large lattices 16A.When a third direction (an m direction) is defined as a directionbisecting the angle between the first and second directions and a fourthdirection (an n direction) is defined as a direction perpendicular tothe third direction, the first connection 22A contains a medium lattice24 having a shape corresponding to k small lattices 18 (in which k is areal number larger than 1) arranged in the fourth direction. A firstabsent portion 60A (a portion provided by removing one side from thesmall lattice 18) is formed on the side 32 of the first large lattice16A perpendicular to the fourth direction adjacent to the medium lattice24. In the example of FIG. 19, the medium lattice 24 has a shapecorresponding to three small lattices 18 arranged in the fourthdirection. Electrically isolated first insulations 28A are disposedbetween the adjacent first conductive patterns 26A.

The first dummy pattern 20A contains a plurality of first auxiliarywires 62A (having an axis direction parallel to the third direction)arranged along the side 32 of the first large lattice 16A perpendicularto the third direction, and a plurality of first auxiliary wires 62A(having an axis direction parallel to the fourth direction) arrangedalong the side 32 of the first large lattice 16A perpendicular to thefourth direction. In the first insulation 28A, two first L-shapedpatterns 64A are arranged facing each other, each of the first L-shapedpatterns 64A being formed by combining two first auxiliary wires 62Ainto an L shape.

The axis-direction length of each first auxiliary wire 62A is ⅘ or less,preferably ½ or less, of the inside side length of the small lattice 18.The first auxiliary wire 62A is positioned at a predetermined distancefrom the first large lattice 16A. The predetermined distance is adifference obtained by subtracting the axis-direction length of thefirst auxiliary wire 62A from the inside side length of the smalllattice 18. For example, when the axis-direction length of the firstauxiliary wire 62A is ⅘ or ½ of the inside side length of the smalllattice 18, the predetermined distance is ⅕ or ½ of the inside sidelength.

As shown in FIG. 17, in the first conductive sheet 10A having theabove-described structure, in one end of each first conductive pattern26A, the first connection 22A is not formed on the open end of the firstlarge lattice 16A. In the other end of the first conductive pattern 26A,the end of the first large lattice 16A is electrically connected to thefirst terminal wiring pattern 42 a composed of the thin metal wire 15 bythe first wire connection 40 a.

Thus, as shown in FIG. 17, in the first conductive sheet 10A used in thetouch panel 100, a large number of the first conductive patterns 26A arearranged in the sensing region 112, and a plurality of the firstterminal wiring patterns 42 a extending from the first wire connections40 a are arranged in the terminal wiring region 114.

On the other hand, as shown in FIGS. 17 and 20, the second conductivepart 13B of the second conductive sheet 10B contains two or more secondconductive patterns 26B and second dummy patterns 20B. The secondconductive patterns 26B each extend in the second direction (the ydirection), are arranged in the first direction (the x direction), andeach contain a large number of lattices. The second dummy patterns 20Bare arranged around the second conductive patterns 26B.

The second conductive pattern 26B contains two or more second largelattices 16B connected in series in the second direction. The secondlarge lattices 16B each contain a combination of two or more smalllattices 18. The above second dummy pattern 20B is formed around eachside 46 of the second large lattice 16B and is not connected to thesecond large lattice 16B.

A second connection 22B is formed between each adjacent two of thesecond large lattices 16B to electrically connect the second largelattices 16B. The second connection 22B contains a medium lattice 24having a shape corresponding to k small lattices 18 (in which k is areal number larger than 1) arranged in the third direction. A secondabsent portion 60B (a portion provided by removing one side from thesmall lattice 18) is formed on the side 46 of the second large lattice16B perpendicular to the third direction adjacent to the medium lattice24.

Electrically isolated second insulations 28B are disposed between theadjacent second conductive patterns 26B.

The second dummy pattern 20B contains a plurality of second auxiliarywires 62B (having an axis direction parallel to the fourth direction)arranged along the side 46 of the second large lattice 16B perpendicularto the fourth direction, and a plurality of second auxiliary wires 62B(having an axis direction parallel to the third direction) arrangedalong the side 46 of the second large lattice 16B perpendicular to thethird direction. In the second insulation 28B, two second L-shapedpatterns 64B are arranged facing each other, each of the second L-shapedpatterns 64B being formed by combining two second auxiliary wires 62Binto an L shape.

The axis-direction length of each second auxiliary wire 62B is ⅘ orless, preferably ½ or less, of the inside side length of the smalllattice 18 like the first auxiliary wire 62A. The second auxiliary wire62B is positioned at a predetermined distance from the second largelattice 16B. The predetermined distance is a difference obtained bysubtracting the axis-direction length of the second auxiliary wire 62Bfrom the inside side length of the small lattice 18 as in the firstauxiliary wire 62A. For example, when the axis-direction length of thesecond auxiliary wire 62B is ⅘ or ½ of the inside side length of thesmall lattice 18, the predetermined distance is ⅕ or ½ of the insideside length.

As shown in FIG. 17, in the second conductive sheet 10B having theabove-described structure, in an end of each second conductive pattern26B, the second connection 22B is not formed on the open end of thesecond large lattice 16B. In the other end of each odd-numbered secondconductive pattern 26B and in the one end of each even-numbered secondconductive pattern 26B, the end of the second large lattice 16B iselectrically connected to the second terminal wiring pattern 42 bcomposed of the thin metal wire 15 by the second wire connection 40 b.

Thus, in the second conductive sheet 10B used in the touch panel 100, alarge number of the second conductive patterns 26B are arranged in thesensing region 112, and a plurality of the second terminal wiringpatterns 42 b extending from the second wire connections 40 b arearranged in the terminal wiring region 114.

For example, as shown in FIG. 21, in a case where the first conductivesheet 10A is stacked on the second conductive sheet 10B to form thefourth laminated conductive sheet 12D, the first conductive patterns 26Aand the second conductive patterns 26B are crossed. Specifically, thefirst connections 22A of the first conductive patterns 26A and thesecond connections 22B of the second conductive patterns 26B arearranged facing each other with the first transparent substrate 14A (seeFIG. 18A) interposed therebetween, and also the first insulations 28A ofthe first conductive part 13A and the second insulations 28B of thesecond conductive part 13B are arranged facing each other with the firsttransparent substrate 14A interposed therebetween.

When the fourth laminated conductive sheet 12D is viewed from above, asshown in FIG. 21, spaces between the first large lattices 16A on thefirst conductive sheet 10A are filled with the second large lattices 16Bon the second conductive sheet 10B. In this case, the first dummypatterns 20A and the second dummy patterns 20B overlap with each otherto form combined patterns 66 between the first large lattices 16A andthe second large lattices 16B. As shown in FIG. 22, in the combinedpattern 66, a first axis line 68A of the first auxiliary wire 62Acorresponds to the second axis line 68B of the second auxiliary wire62B, the first auxiliary wire 62A does not overlap with the secondauxiliary wire 62B, and an end of the first auxiliary wire 62Acorresponds to an end of the second auxiliary wire 62B, to form one sideof the small lattice 18. Thus, the combined pattern 66 contains acombination of two or more small lattices 18 similarly to the innerpatterns of the first large lattice 16A and the second large lattice16B. As a result, when the fourth laminated conductive sheet 12D isviewed from above, as shown in FIG. 21, the sensing region 112 iscovered with a large number of the small lattices 18. As shown in FIG.18A, the projected distance Lf between the side 32 of the first largelattice 16A and the long side 46 of the second large lattice 16B isapproximately equal to the side length of the small lattice 18 toadvantageously lower the parasitic capacitance.

Though not shown in the drawings, the arrangement of the first wireconnections 40 a and the second wire connections 40 b, the arrangementof the first terminal wiring patterns 42 a and the second terminalwiring patterns 42 b in the terminal wiring region 114, and thearrangement of the first terminals 116 a and the second terminals 116 bin the fourth laminated conductive sheet 12D are equal to those in theabove first laminated conductive sheet 12A.

Consequently, when the fourth laminated conductive sheet 12D is used inthe projected capacitive touch panel 100 or the like, the response speedand the size of the touch panel 100 can be easily increased.Furthermore, the boundaries between the first large lattices 16A of thefirst conductive sheet 10A and the second large lattices 16B of thesecond conductive sheet 10B can be made less visible, defects such asthe local line thickening can be prevented, and the overall visibilitycan be improved.

As shown in FIG. 23, the fourth laminated conductive sheet 12D may bedisposed such that the first and second conductive patterns are crossedand displaced in a direction different from the first direction (the xdirection) and the second direction (the y direction). In this case, asat least shown in FIGS. 24A to 25, in the combined pattern 66 formed byarranging the first dummy pattern 20A and the second dummy pattern 20Bfacing each other, the first auxiliary wires 62A and the secondauxiliary wires 62B are not perpendicularly crossed.

Thus, as shown in FIGS. 24A to 24C, in the combined pattern 66, thecombination of the first auxiliary wires 62A arranged along a side ofthe first large lattice 16A and the second auxiliary wires 62B arrangedalong a side of the second large lattice 16B is provided such that thefirst axis line 68A of the first auxiliary wire 62A and the second axisline 68B of the second auxiliary wire 62B are arranged approximately inparallel, and the distance ha between the first axis line 68A and thesecond axis line 68B in the view from above is at least ½ of the smallerline width among the line width Wa of the first auxiliary wire 62A andthe line width Wb of the second auxiliary wire 62B and at most 100 μm(or at most ½ of the arrangement pitch of the small lattices 18).

In FIG. 24A, the distance ha between the first axis line 68A and thesecond axis line 68B is smaller than the total of ½ of the line width Waof the first auxiliary wire 62A and ½ of the line width Wb of the secondauxiliary wire 62B. In this case, the first auxiliary wire 62A and thesecond auxiliary wire 62B partially overlap with each other. In FIG.24B, the distance ha between the first axis line 68A and the second axisline 68B is equal to the total of ½ of the line width Wa of the firstauxiliary wire 62A and ½ of the line width Wb of the second auxiliarywire 62B. In FIG. 24C, the distance ha between the first axis line 68Aand the second axis line 68B is larger than the total of ½ of the linewidth Wa of the first auxiliary wire 62A and ½ of the line width Wb ofthe second auxiliary wire 62B.

In the combined pattern 66, the first auxiliary wires 62A of the twofirst L-shaped patterns 64A in the first insulation 28A and the secondauxiliary wires 62B of the two second L-shaped patterns 64B in thesecond insulation 28B do not form the small lattices 18 but form fourL-shaped patterns (64A, 64A, 64B, 64B).

Thus, as shown in FIG. 25, one second L-shaped pattern 64B is positionedcloser to the two first L-shaped patterns 64A, and the other secondL-shaped pattern 64B is positioned away from the one second L-shapedpattern 64B and the two first L-shaped patterns 64A. The second axisline 68B of one of the two second auxiliary wires 62B in the one secondL-shaped pattern 64B is approximately parallel to the first axis line68A of one of the two first auxiliary wires 62A in one of the two firstL-shaped patterns 64A, and the distance ha between the first axis line68A and the second axis line 68B is at least ½ of the smaller line widthamong the line width Wa of the first auxiliary wire 62A and the linewidth Wb of the second auxiliary wire 62B and at most 100 μm (or at most½ of the arrangement pitch of the small lattices 18).

Similarly, the second axis line 68B of the other second auxiliary wire62B in the one second L-shaped pattern 64B is approximately parallel tothe first axis line 68A of one of the two first auxiliary wires 62A inthe other first L-shaped pattern 64A, and the distance ha between thefirst axis line 68A and the second axis line 68B is at least ½ of thesmaller line width among the line width Wa of the first auxiliary wire62A and the line width Wb of the second auxiliary wire 62B and at most100 μm (or at most ½ of the arrangement pitch of the small lattices 18).The positional relations of the second auxiliary wires 62B and the firstauxiliary wires 62A in the one second L-shaped pattern 64B and the twofirst L-shaped patterns 64A are such as those shown in FIGS. 24A to 24C.

Thus, the first conductive part 13A or the second conductive part 13B isdisplaced by a shift length from the standard position at least in thethird direction, the shift length being at least ½ of the smaller linewidth among the line width Wa of the first auxiliary wire 62A and theline width Wb of the second auxiliary wire 62B and at most 100 μm (or atmost ½ of the arrangement pitch of the small lattices 18). Particularlyin this embodiment, it is displaced by the shift length in each of thethird and fourth directions, the shift length being at least ½ of thesmaller line width among the line width Wa of the first auxiliary wire62A and the line width Wb of the second auxiliary wire 62B and at most100 μm (or at most ½ of the arrangement pitch of the small lattices 18).

The standard position is such a position that, as shown in FIG. 22described above, the first axis line 68A of the first auxiliary wire 62Acorresponds to the second axis line 68B of the second auxiliary wire62B, the first auxiliary wire 62A does not overlap with the secondauxiliary wire 62B, and the end of the first auxiliary wire 62Acorresponds to the end of the second auxiliary wire 62B.

Thus, in the fourth laminated conductive sheet 12D, as shown in FIG. 23,the combined patterns 66 of the first dummy patterns 20A and the seconddummy patterns 20B are arranged between the first large lattices 16A andthe second large lattices 16B, so that blank areas (having a widthcorresponding to the side length of the small lattice 18 and a lengthcorresponding to the side length of the first large lattice 16A or thesecond large lattice 16B) are not formed between the first largelattices 16A and the second large lattices 16B, and the boundariesbetween the first large lattices 16A and the second large lattices 16Bare less visible.

In the combined pattern 66, the first auxiliary wires 62A and the secondauxiliary wires 62B having a length of ½ of the inside side length ofthe small lattices 18 are partially overlapped, and the lengths of theoverlaps are significantly smaller than the side length of the firstlarge lattices 16A and the second large lattices 16B ( 1/20 or less ofthe side length). Therefore, the overlaps of the first auxiliary wires62A and the second auxiliary wires 62B are not highly visible, therebynot deteriorating the visibility. Also the first L-shaped patterns 64Aand the second L-shaped patterns 64B are arranged in the same manner. Asshown in FIG. 25, in the one second L-shaped pattern 64B and the twofirst L-shaped patterns 64A, the first auxiliary wires 62A and thesecond auxiliary wires 62B having the length of ½ of the inside sidelength of the small lattices 18 are partially overlapped, and thelengths of the overlaps are significantly smaller than the side lengthof the first large lattices 16A and the second large lattices 16B ( 1/20or less of the side length). Therefore, the overlaps of the firstauxiliary wires 62A and the second auxiliary wires 62B are not highlyvisible, thereby not deteriorating the visibility.

The first auxiliary wires 62A and the second auxiliary wires 62B mayperpendicularly cross the sides of the second large lattices 16B and thefirst large lattices 16A respectively. Since the axis-direction lengthsof the first auxiliary wires 62A and the second auxiliary wires 62B are½ of the inside side length of the small lattices 18, they are nothighly visible.

The medium lattices 24 of the first connection 22A and the secondconnection 22B are perpendicularly crossed and overlap with each other.In this example, since the first conductive part 13A or the secondconductive part 13B is displaced in the third and fourth directions, thesmall lattices 18 are not uniformly shaped in the overlaps. However, thenumber of the misshapen small lattices 18 is significantly smaller than(approximately 5% of) the number of the small lattices 18 in the firstlarge lattices 16A and the second large lattices 16B around the overlapsof the perpendicularly crossed medium lattices 24 of the firstconnections 22A and the second connections 22B, whereby thenonuniformity of the small lattices 18 are not highly visible.Furthermore, since the first absent portions 60A and the second absentportions 60B are formed adjacent to the medium lattices 24 in the firstlarge lattices 16A and the second large lattices 16B, the straight linesof the medium lattices 24 do not overlap with the straight lines of thefirst large lattices 16A and the second large lattices 16B, and thevisibility is hardly deteriorated.

Therefore, even in a case where the first conductive part 13A or thesecond conductive part 13B is displaced, as described above, theboundaries between the first large lattices 16A of the first conductivesheet 10A and the second large lattices 16B of the second conductivesheet 10B can be made less visible, defects such as the local linethickening can be prevented, and the overall visibility can be improved.In addition, the first large lattices 16A and the second large lattices16B are arranged adjacent to each other to form a regular arrangement ofthe small lattices 18, and the first auxiliary wires 62A or the secondauxiliary wires 62B are displaced to form another arrangement betweenthe first large lattices 16A and the second large lattices 16B, so thatthe different arrangements are combined in the fourth laminatedconductive sheet 12D. Thus, many spatial frequencies are combined,whereby the interference with a pixel array of the liquid crystaldisplay device or the like can be prevented, and the moire generationcan be effectively prevented.

Though the size of the medium lattices 24 in the first connections 22Aand the second connections 22B corresponds to the total of three smalllattices 18 in the above-described first conductive sheet 10A and secondconductive sheet 10B, the size may correspond to 1.5, 2, or 2.5 timesthe size of the small lattices 18, etc. When the medium lattices 24 havean excessively large size, it is difficult to arrange the first largelattices 16A and the second large lattices 16B, and the electrostaticcapacitance change is increased in the overlaps, which should not bedetected. Therefore, the size of the medium lattices 24 is preferably atmost the total size of five small lattices 18.

Also in the fourth laminated conductive sheet 12D, as shown in FIG. 18B,the first conductive part 13A may be formed on one main surface of thefirst transparent substrate 14A, and the second conductive part 13B maybe formed on the other main surface of the first transparent substrate14A.

Though the first conductive sheet 10A and the second conductive sheet10B are used in the projected capacitive touch panel 100 in the aboveembodiments, they can be used in a surface capacitive touch panel or aresistive touch panel.

The first conductive part 13A and the second conductive part 13B may beformed in the following manner. For example, a photosensitive materialhaving the first transparent substrate 14A or the second transparentsubstrate 14B and thereon a photosensitive silver halide-containingemulsion layer is exposed and developed, whereby metallic silverportions and light-transmitting portions are formed in the exposed areasand the unexposed areas respectively to obtain the first conductive part13A or the second conductive part 13B. The metallic silver portions maybe subjected to a physical development treatment and/or a platingtreatment to deposit a conductive metal thereon.

As shown in FIGS. 5B and 18B, the first conductive part 13A may beformed on one main surface of the first transparent substrate 14A, andthe second conductive part 13B may be formed on the other main surfacethereof. In this case, if the one main surface is exposed and then theother main surface is exposed in the usual method, the first conductivepart 13A and the second conductive part 13B often cannot be obtainedwith desired patterns. In particular, it is difficult to uniformly formthe first dummy pattern 20A around the side 32 of the first largelattice 16A and the first insulation pattern 34A in the first insulation28A (shown in FIG. 1, etc.), the second dummy pattern 20B around thelong side 46 of the second large lattice 16B and the second insulationpattern 34B in the second insulation 28B (shown in FIG. 6, etc.), thepattern of a large number of the first auxiliary wires 62A arrangedalong the side 32 of the first large lattice 16A and the first L-shapedpattern 64A in the first insulation 28A (shown in FIG. 19), and thepattern of a large number of the second auxiliary wires 62B arrangedalong the side 46 of the second large lattice 16B and the secondL-shaped pattern 64B in the second insulation 28B (shown in FIG. 20),and the like.

Therefore, the following production method can be preferably used.

Thus, the first conductive part 13A on the one main surface and thesecond conductive part 13B on the other main surface are formed bysubjecting photosensitive silver halide emulsion layers formed on eitherside of the first transparent substrate 14A to one-shot exposure.

A specific example of the production method will be described below withreference to FIGS. 26 to 28.

First, in the step S1 of FIG. 26, a long photosensitive material 140 isprepared. As shown in FIG. 27A, the photosensitive material 140 has thefirst transparent substrate 14A, a photosensitive silver halide emulsionlayer formed on one main surface of the first transparent substrate 14A(hereinafter referred to as the first photosensitive layer 142 a), and aphotosensitive silver halide emulsion layer formed on the other mainsurface of the first transparent substrate 14A (hereinafter referred toas the second photosensitive layer 142 b).

In the step S2 of FIG. 26, the photosensitive material 140 is exposed.In this step, a simultaneous both-side exposure is carried out, theexposure including a first exposure treatment for irradiating the firstphotosensitive layer 142 a on the first transparent substrate 14A with alight in a first exposure pattern and a second exposure treatment forirradiating the second photosensitive layer 142 b on the firsttransparent substrate 14A with a light in a second exposure pattern. Inthe example of FIG. 27B, the first photosensitive layer 142 a isirradiated through a first photomask 146 a with a first light 144 a (aparallel light) and the second photosensitive layer 142 b is irradiatedthrough a second photomask 146 b with a second light 144 b (a parallellight) while conveying the long photosensitive material 140 in onedirection. The first light 144 a is obtained such that a light from afirst light source 148 a is converted to the parallel light by anintermediate first collimator lens 150 a, and the second light 144 b isobtained such that a light from a second light source 148 b is convertedto the parallel light by an intermediate second collimator lens 150 b.Though the two light sources (the first light source 148 a and thesecond light source 148 b) are used in the example of FIG. 27B, only onelight source may be used. In this case, a light from the one lightsource may be divided by an optical system into the first light 144 aand the second light 144 b for exposing the first photosensitive layer142 a and the second photosensitive layer 142 b.

In the step S3 of FIG. 26, the exposed photosensitive material 140 isdeveloped to produce the first laminated conductive sheet 12A shown inFIG. 5B, etc. The first laminated conductive sheet 12A has the firsttransparent substrate 14A, the first conductive part 13A (including thefirst conductive patterns 26A) formed in the first exposure pattern onthe one main surface of the first transparent substrate 14A, and thesecond conductive part 13B (including the second conductive patterns26B) formed in the second exposure pattern on the other main surface ofthe first transparent substrate 14A. Preferred exposure time anddevelopment time for the first photosensitive layer 142 a and the secondphotosensitive layer 142 b vary depending on the types of the firstlight source 148 a, the second light source 148 b, and a developer,etc., and cannot be categorically determined. The exposure time anddevelopment time may be selected in view of achieving a developmentratio of 100%.

As shown in FIG. 28, in the first exposure treatment in the productionmethod of this embodiment, for example, the first photomask 146 a isplaced in close contact with the first photosensitive layer 142 a, thefirst light source 148 a is arranged facing the first photomask 146 a,and the first light 144 a is emitted from the first light source 148 atoward the first photomask 146 a, so that the first photosensitive layer142 a is exposed. The first photomask 146 a has a glass substratecomposed of a transparent soda glass and a mask pattern (a firstexposure pattern 152 a) formed thereon. Therefore, in the first exposuretreatment, areas in the first photosensitive layer 142 a, correspondingto the first exposure pattern 152 a in the first photomask 146 a, areexposed. A space of approximately 2 to 10 μm may be formed between thefirst photosensitive layer 142 a and the first photomask 146 a.

Similarly, in the second exposure treatment, for example, the secondphotomask 146 b is placed in close contact with the secondphotosensitive layer 142 b, the second light source 148 b is arrangedfacing the second photomask 146 b, and the second light 144 b is emittedfrom the second light source 148 b toward the second photomask 146 b, sothat the second photosensitive layer 142 b is exposed. The secondphotomask 146 b, as well as the first photomask 146 a, has a glasssubstrate composed of a transparent soda glass and a mask pattern (asecond exposure pattern 152 b) formed thereon. Therefore, in the secondexposure treatment, areas in the second photosensitive layer 142 b,corresponding to the second exposure pattern 152 b in the secondphotomask 146 b, are exposed. In this case, a space of approximately 2to 10 μm may be formed between the second photosensitive layer 142 b andthe second photomask 146 b.

In the first and second exposure treatments, the emission of the firstlight 144 a from the first light source 148 a and the emission of thesecond light 144 b from the second light source 148 b may be carried outsimultaneously or independently. In a case where the emissions aresimultaneously carried out, the first photosensitive layer 142 a and thesecond photosensitive layer 142 b can be simultaneously exposed in oneexposure process, resulting in reduction of the treatment time.

In a case where both of the first photosensitive layer 142 a and thesecond photosensitive layer 142 b are not spectrally sensitized, a lightincident on one side may affect the image formation on the other side(the back side) in the both-side exposure of the photosensitive material140.

Thus, the first light 144 a from the first light source 148 a reachesthe first photosensitive layer 142 a and is scattered by silver halideparticles in the first photosensitive layer 142 a, and a part of thescattered light is transmitted through the first transparent substrate14A and reaches the second photosensitive layer 142 b. Then, a largearea of the boundary between the second photosensitive layer 142 b andthe first transparent substrate 14A is exposed to form a latent image.As a result, the second photosensitive layer 142 b is exposed to thesecond light 144 b from the second light source 148 b and the firstlight 144 a from the first light source 148 a. In a case where thesecond photosensitive layer 142 b is developed to prepare the firstlaminated conductive sheet 12A, the conductive pattern corresponding tothe second exposure pattern 152 b (the second conductive part 13B) isformed, and additionally a thin conductive layer is formed due to thefirst light 144 a from the first light source 148 a between theconductive patterns, so that the desired pattern (corresponding to thesecond exposure pattern 152 b) cannot be obtained. This is true also forthe first photosensitive layer 142 a.

As a result of intense research in view of solving this problem, it hasbeen found that if the thicknesses and the applied silver amounts of thefirst photosensitive layer 142 a and the second photosensitive layer 142b are selected within particular ranges, the incident light can beabsorbed by the silver halide to suppress the light transmission to theback side. In this embodiment, the thicknesses of the firstphotosensitive layer 142 a and the second photosensitive layer 142 b maybe 1 to 4 μm. The upper limit is preferably 2.5 μm. The applied silveramounts of the first photosensitive layer 142 a and the secondphotosensitive layer 142 b may be 5 to 20 g/m².

In the above-described both-side contact exposure technology, theexposure may be inhibited by dust or the like attached to the filmsurface so that an image defect is generated. It is known that the dustattachment can be prevented by applying a conductive substance such as ametal oxide or a conductive polymer to the film. However, the metaloxide or the like remaining in the processed product deteriorates thetransparency of the final product, and the conductive polymer isdisadvantageous in storage stability, etc. As a result of intenseresearch, it has been found that a silver halide layer with reducedbinder content exhibits a satisfactory conductivity for static chargeprevention. Thus, the volume ratio of silver/binder is limited in thefirst photosensitive layer 142 a and the second photosensitive layer 142b. The silver/binder volume ratios of the first photosensitive layer 142a and the second photosensitive layer 142 b are 1/1 or more, preferably2/1 or more.

In a case where the thicknesses, the applied silver amounts, and thesilver/binder volume ratios of the first photosensitive layer 142 a andthe second photosensitive layer 142 b are selected as described above,the first light 144 a emitted from the first light source 148 a to thefirst photosensitive layer 142 a does not reach the secondphotosensitive layer 142 b as shown in FIG. 28. Similarly, the secondlight 144 b emitted from the second light source 148 b to the secondphotosensitive layer 142 b does not reach the first photosensitive layer142 a. As a result, in the following development for producing the firstlaminated conductive sheet 12A, as shown in FIG. 5B, only the conductivepattern corresponding to the first exposure pattern 152 a (the patternof the first conductive part 13A) is formed on the one main surface ofthe first transparent substrate 14A, and only the conductive patterncorresponding to the second exposure pattern 152 b (the pattern of thesecond conductive part 13B) is formed on the other main surface of thefirst transparent substrate 14A, so that the desired patterns can beobtained.

In the production method using the above one-shot both-side exposure,the first photosensitive layer 142 a and the second photosensitive layer142 b can have both of the satisfactory conductivity and both-sideexposure suitability, and the same or different patterns can be formedon either side of the first transparent substrate 14A by the exposure,whereby the electrodes of the touch panel 100 can be easily formed, andthe touch panel 100 can be made thinner (smaller).

In the above production method, the first conductive patterns 26A andthe second conductive patterns 26B are formed using the photosensitivesilver halide emulsion layer. The other examples of the productionmethods include the following methods.

A photoresist film disposed on a copper foil on the first transparentsubstrate 14A or the second transparent substrate 14B may be exposed anddeveloped to form a resist pattern, and the copper foil exposed from theresist pattern may be etched to obtain the first conductive patterns 26Aand the second conductive patterns 26B.

Alternatively, a paste containing fine metal particles may be printed onthe first transparent substrate 14A or the second transparent substrate14B, and the printed paste may be plated with a metal to obtain thefirst conductive patterns 26A and the second conductive patterns 26B.

The first conductive patterns 26A and the second conductive patterns 26Bmay be printed on the first transparent substrate 14A and the secondtransparent substrate 14B by using a screen or gravure printing plate.

The first conductive patterns 26A and the second conductive patterns 26Bmay be formed on the first transparent substrate 14A and the secondtransparent substrate 14B by using an inkjet method.

A particularly preferred method, which contains using a photographicphotosensitive silver halide material for producing the first conductivesheet 10A and the second conductive sheet 10B according to thisembodiment, will be mainly described below.

The method for producing the first conductive sheet 10A and the secondconductive sheet 10B of this embodiment includes the following threeprocesses different in the photosensitive materials and developmenttreatments.

(1) A process comprising subjecting a photosensitive black-and-whitesilver halide material free of physical development nuclei to a chemicalor thermal development to form the metallic silver portions on thematerial.

(2) A process comprising subjecting a photosensitive black-and-whitesilver halide material having a silver halide emulsion layer containingphysical development nuclei to a solution physical development to formthe metallic silver portions on the material.

(3) A process comprising subjecting a stack of a photosensitiveblack-and-white silver halide material free of physical developmentnuclei and an image-receiving sheet having a non-photosensitive layercontaining physical development nuclei to a diffusion transferdevelopment to form the metallic silver portions on thenon-photosensitive image-receiving sheet.

In the process of (1), an integral black-and-white development procedureis employed to form a transmittable conductive film such as alight-transmitting conductive film on the photosensitive material. Theresulting silver is a chemically or thermally developed silvercontaining a high-specific surface area filament, and thereby shows ahigh activity in the following plating or physical developmenttreatment.

In the process of (2), the silver halide particles are melted around anddeposited on the physical development nuclei in the exposed areas toform a transmittable conductive film such as a light-transmittingconductive film on the photosensitive material. Also in this process, anintegral black-and-white development procedure is employed. Though highactivity can be achieved since the silver halide is deposited on thephysical development nuclei in the development, the developed silver hasa spherical shape with small specific surface.

In the process of (3), the silver halide particles are melted in theunexposed areas, and are diffused and deposited on the developmentnuclei of the image-receiving sheet, to form a transmittable conductivefilm such as a light-transmitting conductive film on the sheet. In thisprocess, a so-called separate-type procedure is employed, theimage-receiving sheet being peeled off from the photosensitive material.

A negative or reversal development treatment can be used in theprocesses. In the diffusion transfer development, the negativedevelopment treatment can be carried out using an auto-positivephotosensitive material.

The chemical development, thermal development, solution physicaldevelopment, and diffusion transfer development have the meaningsgenerally known in the art, and are explained in common photographicchemistry texts such as Shin-ichi Kikuchi, “Shashin Kagaku (PhotographicChemistry)”, Kyoritsu Shuppan Co., Ltd., 1955 and C. E. K. Mees, “TheTheory of Photographic Processes, 4th ed.”, Mcmillan, 1977. A liquidtreatment is generally used in the present invention, and also a thermaldevelopment treatment may be utilized. For example, techniques describedin Japanese Laid-Open Patent Publication Nos. 2004-184693, 2004-334077,and 2005-010752 and Japanese Patent Application Nos. 2004-244080 and2004-085655 can be used in the present invention.

The structure of each layer in the first conductive sheet 10A and thesecond conductive sheet 10B of this embodiment will be described indetail below.

[First Transparent Substrate 14A and Second Transparent Substrate 14B]

The first transparent substrate 14A and the second transparent substrate14B may be a plastic film, a plastic plate, a glass plate, etc.

Examples of materials for the plastic film and the plastic plate includepolyesters such as polyethylene terephthalates (PET) and polyethylenenaphthalates (PEN); polyolefins such as polyethylenes (PE),polypropylenes (PP), polystyrenes, and EVA; vinyl resins; polycarbonates(PC); polyamides; polyimides; acrylic resins; and triacetyl celluloses(TAC).

The first transparent substrate 14A and the second transparent substrate14B are preferably a film or plate of a plastic having a melting pointof about 290° C. or lower, such as PET (melting point 258° C.), PEN(melting point 269° C.), PE (melting point 135° C.), PP (melting point163° C.), polystyrene (melting point 230° C.), polyvinyl chloride(melting point 180° C.), polyvinylidene chloride (melting point 212°C.), or TAC (melting point 290° C.). The PET is particularly preferredfrom the viewpoints of light transmittance, workability, etc. Theconductive film such as the first conductive sheet 10A or the secondconductive sheet 10B used in the first to third laminated conductivesheets 12A to 12C is required to be transparent, and therefore the firsttransparent substrate 14A and the second transparent substrate 14Bpreferably have a high transparency.

[Silver Salt Emulsion Layer]

The silver salt emulsion layer to be converted to a conductive layer inthe first conductive sheet 10A and the second conductive sheet 10B (aconductive portion such as the first large lattice 16A, the firstconnection 22A, the first insulation pattern 34A in the first insulation28A, the second large lattice 16B, the second connection 22B, the secondinsulation pattern 34B in the second insulation 28B, or the smalllattice 18) contains a silver salt and a binder and may further containa solvent and an additive such as a dye.

The silver salt used in this embodiment may be an inorganic silver saltsuch as a silver halide or an organic silver salt such as silveracetate. In this embodiment, the silver halide is preferred because ofits excellent light sensing property.

The applied silver amount (the amount of the applied silver salt in thesilver density) of the silver salt emulsion layer is preferably 1 to 30g/m², more preferably 1 to 25 g/m², further preferably 5 to 20 g/m².When the applied silver amount is within this range, the resultant firstto third laminated conductive sheets 12A to 12C can exhibit a desiredsurface resistance.

Examples of the binders used in this embodiment include gelatins,polyvinyl alcohols (PVA), polyvinyl pyrolidones (PVP), polysaccharidessuch as starches, celluloses and derivatives thereof, polyethyleneoxides, polyvinylamines, chitosans, polylysines, polyacrylic acids,polyalginic acids, polyhyaluronic acids, and carboxycelluloses. Thebinders show a neutral, anionic, or cationic property depending on theionicity of the functional group.

In this embodiment, the amount of the binder in the silver salt emulsionlayer is not particularly limited, and may be appropriately selected toobtain sufficient dispersion and adhesion properties. The volume ratioof silver/binder in the silver salt emulsion layer is preferably ¼ ormore, more preferably ½ or more. The silver/binder volume ratio ispreferably 100/1 or less, more preferably 50/1 or less. Particularly,the silver/binder volume ratio is further preferably 1/1 to 4/1, mostpreferably 1/1 to 3/1. When the silver/binder volume ratio of the silversalt emulsion layer is within the range, the resistance variation can bereduced even under various applied silver amount, whereby the first tothird laminated conductive sheets 12A to 12C can be produced with auniform surface resistance. The silver/binder volume ratio can beobtained by converting the silver halide/binder weight ratio of thematerial to the silver/binder weight ratio, and by further convertingthe silver/binder weight ratio to the silver/binder volume ratio.

<Solvent>

The solvent used for forming the silver salt emulsion layer is notparticularly limited, and examples thereof include water, organicsolvents (e.g. alcohols such as methanol, ketones such as acetone,amides such as formamide, sulfoxides such as dimethyl sulfoxide, esterssuch as ethyl acetate, ethers), ionic liquids, and mixtures thereof.

In this embodiment, the ratio of the solvent to the total of the silversalt, the binder, and the like in the silver salt emulsion layer is 30%to 90% by mass, preferably 50% to 80% by mass.

<Other Additives>

The additive used in this embodiment is not particularly limited, andmay be preferably selected from known additives.

[Other Layers]

A protective layer (not shown) may be formed on the silver salt emulsionlayer. The protective layer used in this embodiment contains a bindersuch as a gelatin or a high-molecular polymer, and is disposed on thephotosensitive silver salt emulsion layer to improve the scratchprevention or mechanical property. The thickness of the protective layeris preferably 0.5 μm or less. The method of applying or forming theprotective layer is not particularly limited, and may be appropriatelyselected from known applying or forming methods. In addition, anundercoat layer or the like may be formed below the silver salt emulsionlayer.

The steps for producing the first conductive sheet 10A and the secondconductive sheet 10B will be described below.

[Exposure]

In this embodiment, the first conductive patterns 26A and the secondconductive patterns 26B may be formed in a printing process, and may beformed by exposure and development treatments, etc. in another process.Thus, a photosensitive material having the first transparent substrate14A or the second transparent substrate 14B and thereon the silversalt-containing layer or a photosensitive material coated with aphotopolymer for photolithography is subjected to the exposuretreatment. An electromagnetic wave may be used in the exposure. Forexample, the electromagnetic wave may be a light such as a visible lightor an ultraviolet light, or a radiation ray such as an X-ray. Theexposure may be carried out using a light source having a wavelengthdistribution or a specific wavelength.

[Development Treatment]

In this embodiment, the emulsion layer is subjected to the developmenttreatment after the exposure. Common development treatment technologiesfor photographic silver salt films, photographic papers, print engravingfilms, emulsion masks for photomasking, and the like may be used in thepresent invention. The developer used in the development treatment isnot particularly limited, and may be a PQ developer, an MQ developer, anMAA developer, etc. Examples of commercially available developers usablein the present invention include CN-16, CR-56, CP45X, FD-3, and PAPITOLavailable from FUJIFILM Corporation, C-41, E-6, RA-4, D-19, and D-72available from Eastman Kodak Company, and developers contained in kitsthereof. The developer may be a lith developer.

In the present invention, the development process may include a fixationtreatment for removing the silver salt in the unexposed areas tostabilize the material. Fixation treatment technologies for photographicsilver salt films, photographic papers, print engraving films, emulsionmasks for photomasking, and the like may be used in the presentinvention.

In the fixation treatment, the fixation temperature is preferably about20° C. to 50° C., more preferably 25° C. to 45° C. The fixation time ispreferably 5 seconds to 1 minute, more preferably 7 to 50 seconds. Theamount of the fixer used is preferably 600 ml/m² or less, morepreferably 500 ml/m² or less, particularly preferably 300 ml/m² or less,per 1 m² of the photosensitive material treated.

The developed and fixed photosensitive material is preferably subjectedto a water washing treatment or a stabilization treatment. The amount ofwater used in the water washing or stabilization treatment is generally20 L or less, and may be 3 L or less, per 1 m² of the photosensitivematerial. The water amount may be 0, and thus the photosensitivematerial may be washed with storage water.

The ratio of the metallic silver contained in the exposed areas afterthe development to the silver contained in the areas before the exposureis preferably 50% or more, more preferably 80% or more by mass. When theratio is 50% or more by mass, a high conductivity can be achieved.

In this embodiment, the tone (gradation) obtained by the development ispreferably more than 4.0, though not particularly restrictive. When thetone is more than 4.0 after the development, the conductivity of theconductive metal portion can be increased while maintaining the hightransmittance of the light-transmitting portion. For example, the toneof 4.0 or more can be obtained by doping with rhodium or iridium ion.

The conductive sheet is obtained by the above steps. The surfaceresistance of the resultant conductive sheet is preferably within therange of 0.1 to 100 ohm/sq. The lower limit is preferably 1 ohm/sq ormore, 3 ohm/sq or more, 5 ohm/sq or more, or 10 ohm/sq. The upper limitis preferably 70 ohm/sq or less or 50 ohm/sq or less. When the surfaceresistance is controlled within this range, the position detection canbe performed even in a large touch panel having an area of 10 cm×10 cmor more. The conductive sheet may be subjected to a calender treatmentafter the development treatment to obtain a desired surface resistance.

[Physical Development Treatment and Plating Treatment]

In this embodiment, to increase the conductivity of the metallic silverportion formed by the above exposure and development treatments,conductive metal particles may be deposited thereon by a physicaldevelopment treatment and/or a plating treatment. In the presentinvention, the conductive metal particles may be deposited on themetallic silver portion by only one of the physical development andplating treatments or by the combination of the treatments. The metallicsilver portion, subjected to the physical development treatment and/orthe plating treatment in this manner, is also referred to as theconductive metal portion.

In this embodiment, the physical development is such a process thatmetal ions such as silver ions are reduced by a reducing agent, wherebymetal particles are deposited on a metal or metal compound core. Suchphysical development has been used in the fields of instant B & W film,instant slide film, printing plate production, etc., and thetechnologies can be used in the present invention.

The physical development may be carried out at the same time as theabove development treatment after the exposure, and may be carried outafter the development treatment separately.

In this embodiment, the plating treatment may contain electrolessplating (such as chemical reduction plating or displacement plating),electrolytic plating, or a combination thereof. Known electrolessplating technologies for printed circuit boards, etc. may be used inthis embodiment. The electroless plating is preferably electrolesscopper plating.

[Oxidation Treatment]

In this embodiment, the metallic silver portion formed by thedevelopment treatment or the conductive metal portion formed by thephysical development treatment and/or the plating treatment ispreferably subjected to an oxidation treatment. For example, by theoxidation treatment, a small amount of a metal deposited on thelight-transmitting portion can be removed, so that the transmittance ofthe light-transmitting portion can be increased to approximately 100%.

[Conductive Metal Portion]

In this embodiment, as described above, the lower limit of the linewidth of the conductive metal portion is preferably 1 μm or more, 3 μmor more, 4 μm or more, or 5 μm or more, and the upper limit thereof ispreferably 15 μm or less, 10 μm or less, 9 μm or less, or 8 μm or less.In a case where the line width is less than the lower limit, theconductive metal portion has an insufficient conductivity, whereby atouch panel using the conductive part has an insufficient detectionsensitivity. On the other hand, in a case where the line width is morethan the upper limit, moire is significantly generated due to theconductive metal portion, and a touch panel using the conductive parthas a poor visibility. In a case where the line width is within theabove range, the moire of the conductive metal portion is improved, andthe visibility is remarkably improved. The line distance (the distancebetween the sides facing each other in the small lattice 18) ispreferably 30 to 500 μm, more preferably 50 to 400 μm, most preferably100 to 350 μm. The conductive metal portion may have a part with a linewidth of more than 200 μm for the purpose of ground connection, etc.

In this embodiment, the opening ratio of the conductive metal portion ispreferably 85% or more, more preferably 90% or more, most preferably 95%or more, in view of the visible light transmittance. The opening ratiois the ratio of the light-transmitting portions other than theconductive portions such as the first large lattices 16A, the firstconnections 22A, the first insulation patterns 34A in the firstinsulations 28A, the second large lattices 16B, the second connections22B, the second insulation patterns 34B in the second insulations 28B,the small lattices 18, and the like to the entire surface. For example,a square lattice having a line width of 15 μm and a pitch of 300 μm hasan opening ratio of 90%.

[Light-Transmitting Portion]

In this embodiment, the light-transmitting portion is a portion havinglight transmittance, other than the conductive metal portions in thefirst conductive sheet 10A and the second conductive sheet 10B. Thetransmittance of the light-transmitting portion, which is herein aminimum transmittance value in a wavelength region of 380 to 780 nmobtained neglecting the light absorption and reflection of the firsttransparent substrate 14A and the second transparent substrate 14B, is90% or more, preferably 95% or more, more preferably 97% or more,further preferably 98% or more, most preferably 99% or more.

The exposure is preferably carried out using a glass mask method or alaser lithography pattern exposure method.

[First Conductive Sheet 10A and Second Conductive Sheet 10B]

In the first conductive sheet 10A and the second conductive sheet 10B ofthis embodiment, the thicknesses of the first transparent substrate 14Aand the second transparent substrate 14B are preferably 5 to 350 μm,more preferably 30 to 150 μm. In a case where the thicknesses are 5 to350 μm, a desired visible light transmittance can be obtained, and thesubstrates can be easily handled.

The thickness of the metallic silver portion formed on the firsttransparent substrate 14A or the second transparent substrate 14B may beappropriately selected by controlling the thickness of the coatingliquid for the silver salt-containing layer applied to the substrate.The thickness of the metallic silver portion may be selected within arange of 0.001 to 0.2 mm, and is preferably 30 μm or less, morepreferably 20 μm or less, further preferably 0.01 to 9 μm, mostpreferably 0.05 to 5 μm. The metallic silver portion is preferablyformed in a patterned shape. The metallic silver portion may have amonolayer structure or a multilayer structure containing two or morelayers. In a case where the metallic silver portion has a patternedmultilayer structure containing two or more layers, the layers may havedifferent wavelength color sensitivities. In this case, differentpatterns can be formed in the layers by using exposure lights withdifferent wavelengths.

In a touch panel, the conductive metal portion preferably has a smallerthickness. As the thickness is reduced, the viewing angle and visibilityof the display panel are improved. Thus, the thickness of the layer ofthe conductive metal deposited on the conductive metal portion ispreferably less than 9 μm, more preferably 0.1 μm or more but less than5 μm, further preferably 0.1 μm or more but less than 3 μm.

In this embodiment, the thickness of the metallic silver portion can becontrolled by changing the coating thickness of the silversalt-containing layer, and the thickness of the conductive metalparticle layer can be controlled in the physical development treatmentand/or the plating treatment, whereby the first conductive sheet 10A andthe second conductive sheet 10B can be easily produced with a thicknessof less than 5 μm (preferably less than 3 μm).

The plating or the like is not necessarily carried out in the method forproducing the first conductive sheet 10A and the second conductive sheet10B of this embodiment. This is because the desired surface resistancecan be obtained by controlling the applied silver amount and thesilver/binder volume ratio of the silver salt emulsion layer in themethod. The calender treatment or the like may be carried out ifnecessary.

(Film Hardening Treatment after Development Treatment)

It is preferred that after the silver salt emulsion layer is developed,the resultant is immersed in a hardener and thus subjected to a filmhardening treatment. Examples of the hardeners include boric acid anddialdehydes such as 2,3-dihydroxy-1,4-dioxane, glutaraldehyde andadipaldehyde, described in Japanese Laid-Open Patent Publication No.02-141279.

[Laminated Conductive Sheet]

The antireflection film 126 may be attached to the laminated conductivesheet. In this case, a structure according to the above first to thirdstructure examples of FIGS. 8A to 8C can be preferably used.

For example, the antireflection film 126 is prepared by forming the hardcoat layer 122 and the antireflection layer 124 on the first laminatedconductive sheet 12A (see the first and second structure examples) or byforming the transparent film 130, the hard coat layer 122, and theantireflection layer 124 on the first laminated conductive sheet 12A(see the third structure example).

A preferred embodiment of the antireflection film 126 will be describedbelow mainly with respect to the third structure example.

<Transparent Film 130>

The transparent film 130 is used on the viewer side of the displaydevice 108, and therefore has to be a colorless film having a high lighttransmittance and an excellent transparency. The transparent film 130 ispreferably a plastic film. Examples of polymers for the plastic filminclude cellulose acylates (e.g., cellulose triacetates such asTAC-TD80U and TD80UF available from FUJIFILM Corporation, cellulosediacetates, cellulose acetate propionates, cellulose acetate butylates),polyamides, polycarbonates, polyesters (e.g., polyethyleneterephthalates, polyethylene naphthalates), polystyrenes, polyolefins,norbornene resins (e.g., ARTON (trade name) available from JSRCorporation), amorphous polyolefins (e.g., ZEONEX (trade name) availablefrom Zeon Corporation), and (meth)acrylic resins (e.g., ACRYPET VRL20A(trade name) available from Mitsubishi Rayon Co., Ltd., ringstructure-containing acrylic resins described in Japanese Laid-OpenPatent Publication Nos. 2004-070296 and 2006-171464). Among thepolymers, the cellulose triacetates, cellulose acetate propionates,cellulose acetate butylates, polyethylene terephthalates, andpolyethylene naphthalates are preferred, and the cellulose triacetatesare particularly preferred.

<Hard Coat Layer 122>

The hard coat layer 122 is preferably formed in the antireflection film126 to improve the physical strength.

The hard coat layer 122 may contain two or more layers stacked.

The refractive index of the hard coat layer 122 is preferably 1.48 to1.90, more preferably 1.50 to 1.80, further preferably 1.52 to 1.65, inview of optical design for achieving the antireflection property. Inthis embodiment, at least one low refractive index layer is disposed onthe hard coat layer 122. Therefore, in a case where the refractive indexof the hard coat layer 122 is lower than the above range, theantireflection property tends to be deteriorated. On the other hand, ina case where the refractive index is higher than the above range, thecolor of the reflected light tends to be heightened.

The thickness of the hard coat layer 122 is generally about 0.5 to 50μm, preferably 1 to 20 μm, more preferably 2 to 15 μm, most preferably 3to 10 μm, in view of sufficiently improving the durability and impactresistance of the antireflection film 126. The strength of the hard coatlayer 122 is preferably 2H or more, more preferably 3H or more, mostpreferably 4H or more, in a pencil hardness test. Furthermore, a sampleof the hard coat layer 122 preferably exhibits a smaller wear amount ina Taber test in accordance with JIS K 5400.

The hard coat layer 122 is preferably formed by a crosslinking orpolymerization reaction of an ionizing radiation-curable compound. Forexample, the hard coat layer 122 may be formed by applying a compositioncontaining an ionizing radiation-curable multifunctional monomer oroligomer to the transparent film 130 and by crosslinking or polymerizingthe multifunctional monomer or oligomer. A functional group of theionizing radiation-curable multifunctional monomer or oligomer ispreferably a photo-, electron beam-, or radiation-polymerizable group,particularly a photo-polymerizable group. The photo-polymerizable groupmay be an unsaturated group such as a (meth)acryloyl group, a vinylgroup, a styryl group, or an allyl group, etc., and the (meth)acryloylgroup is most preferable. Specifically, the compound may be a monomerdescribed in Paragraphs [0087] and [0088] of Japanese Laid-Open PatentPublication No. 2006-030740, which may be hardened by a method describedin Paragraph [0089] of this document. A photopolymerization initiatordescribed in Paragraphs [0090] to [0093] of this document may be used inthe photopolymerization.

The hard coat layer 122 may contain matting particles such as inorganiccompound particles or resin particles having an average particlediameter of 1.0 to 10.0 μm (preferably 1.5 to 7.0 μm) to obtain aninternal scattering property. The matting particles may be selected fromthose described in Paragraph [0114] of Japanese Laid-Open PatentPublication No. 2006-030740.

A binder of the hard coat layer 122 may contain a high refractive indexmonomer, fine inorganic particles (having a primary particle diameter of10 to 200 nm not to cause light scattering), or both thereof to controlthe refractive index of the hard coat layer 122. The fine inorganicparticles have an effect of reducing the cure shrinkage due to thecrosslinking reaction in addition to the effect of controlling therefractive index. The fine inorganic particles may be composed of acompound described as an inorganic filler in Paragraph [0120] ofJapanese Laid-Open Patent Publication No. 2006-030740.

<Antireflection Layer 124>

The antireflection film 126 contains the above hard coat layer 122 andthe antireflection layer 124 formed thereon, and may contain thetransparent film 130 as an underlayer. The antireflection layer 124preferably has a refractive index and an optical thickness in thefollowing manner to utilize an optical interference. The antireflectionfilm 126 may contain only one antireflection layer 124, and may containa stack of a plurality of the antireflection layers 124 to obtain alower reflectance. In the case of using the stack of a plurality of theantireflection layers 124, optical interference layers having differentrefractive indices may be alternately stacked, and two or more opticalinterference layers having different refractive indices may be stacked.Specifically, the antireflection film 126 preferably has such astructure that only a low refractive index layer is formed on the hardcoat layer 122, that a high refractive index layer and a low refractiveindex layer are formed in this order on the hard coat layer 122, or thata middle refractive index layer, a high refractive index layer, and alow refractive index layer are formed in this order on the hard coatlayer 122. It should be noted that the terms “low”, “middle”, and “high”of the refractive index layers represent relative magnitude relations ofthe refractive indices. The refractive index of the low refractive indexlayer is preferably lower than that of the hard coat layer 122. In acase where the refractive index difference between the low refractiveindex layer and the hard coat layer 122 is excessively small, theantireflection property tends to be deteriorated. In a case where therefractive index difference is excessively large, the color of thereflected light tends to be heightened. The refractive index differencebetween the low refractive index layer and the hard coat layer 122 ispreferably 0.01 to 0.40, more preferably 0.05 to 0.30.

The refractive index and the thickness of each layer preferably satisfythe following conditions.

The refractive index of the low refractive index layer is preferably1.20 to 1.46, more preferably 1.25 to 1.42, particularly preferably 1.30to 1.38. The thickness of the low refractive index layer is preferably50 to 150 nm, more preferably 70 to 120 nm.

In a structure where the low refractive index layer is stacked on thehigh refractive index layer to prepare the antireflection film 126, therefractive index of the high refractive index layer is preferably 1.55to 2.40, more preferably 1.60 to 2.20, further preferably 1.65 to 2.10,most preferably 1.80 to 2.00.

In a structure where the middle refractive index layer, the highrefractive index layer, and the low refractive index layer are stackedin this order on the transparent film 130 (or the touch panel 100) toprepare the antireflection film 126, the refractive index of the highrefractive index layer is preferably 1.65 to 2.40, further preferably1.70 to 2.20. The refractive index of the middle refractive index layeris controlled to an intermediate value between the refractive indices ofthe low and high refractive index layers. The refractive index of themiddle refractive index layer is preferably 1.55 to 1.80. The high andmiddle refractive index layers may have optical thicknesses selecteddepending on the refractive indices.

[Low Refractive Index Layer]

The low refractive index layer is preferably hardened after the layerformation. The haze of the low refractive index layer is preferably 3%or less, more preferably 2% or less, most preferably 1% or less.

The low refractive index layer according to the embodiment of thepresent invention is preferably formed from a composition containing atleast (1) a fluorine-containing polymer having a crosslinkable orpolymerizable functional group, (2) a hydrolytic condensation product ofa fluorine-containing organosilane material as a main component, or (3)a monomer having two or more ethylenic unsaturated groups and a fineinorganic particle having a hollow structure.

(1) Fluorine-Containing Compound Having Crosslinkable or PolymerizableFunctional Group

The fluorine-containing compound having the crosslinkable orpolymerizable functional group may be a copolymer of afluorine-containing monomer and a monomer having the crosslinkable orpolymerizable functional group.

Specifically, the fluorine-containing compound may be a copolymer havinga main chain of only carbon atoms and containing a polymerization unitof a fluorine-containing vinyl monomer and a polymerization unit havinga (meth)acryloyl group in a side chain, and examples of such copolymersinclude P-1 to P-40 described in Paragraphs [0043] to [0047] of JapaneseLaid-Open Patent Publication No. 2004-045462. The fluorine-containingcompound may be a fluorine-containing polymer having a siliconecomponent for improving the abrasion resistance and lubricity, such as agraft polymer containing a fluorine atom in a main chain and containinga polymerization unit having a polysiloxane moiety in a side chain, andexamples of such graft polymers include compounds described in Tables 1and 2 in Paragraphs [0074] to [0076] of Japanese Laid-Open PatentPublication No. 2003-222702. Furthermore, the fluorine-containingcompound may be an ethylenic unsaturated group-containing fluoropolymercontaining a structural unit derived from a polysiloxane compound in amain chain, and examples of such fluoropolymers include compoundsdescribed in Japanese Laid-Open Patent Publication No. 2003-183322.

A hardener having a polymerizable unsaturated group may be appropriatelyused in combination with the above polymer as described in JapaneseLaid-Open Patent Publication No. 2000-017028. Also a multifunctionalfluorine-containing compound having a polymerizable unsaturated groupmay be preferably used in combination with the above polymer asdescribed in Japanese Laid-Open Patent Publication No. 2002-145952.Examples of such multifunctional compounds having the polymerizableunsaturated group include the above-described monomers having two ormore ethylenic unsaturated groups. Furthermore, also a hydrolyticcondensation product of an organosilane (particularly an organosilanehaving a (meth)acryloyl group) described in Japanese Laid-Open PatentPublication No. 2004-170901 may be preferably used. In a case where theabove polymer has the polymerizable unsaturated group, the compounds areparticularly preferably used in combination with the polymer to exhibita large effect of improving the abrasion resistance.

When the polymer per se does not have a satisfactory hardening propertyalone, a crosslinkable compound may be added thereto to obtain thesatisfactory hardening property. For example, in a case where thepolymer has a hydroxyl group, an amino compound may be preferably usedas a hardener. The amino compound used as the crosslinkable compound maybe a compound having one or both of a hydroxyalkylamino group and analkoxyalkylamino group, the number of the groups in the compound beingtwo or more in total. Specific examples of such compounds includemelamine compounds, urea compounds, benzoguanamine compounds, andglycoluril compounds. The compound is preferably hardened with anorganic acid or a salt thereof.

(2) Hydrolytic Condensation Product of Fluorine-Containing OrganosilaneMaterial

Also the composition containing the hydrolytic condensation product ofthe fluorine-containing organosilane compound as a main component ispreferred because of its low refractive index and high coating surfacehardness. The hydrolytic condensation product is preferably acondensation product of a tetraalkoxysilane and a compound having ahydrolyzable silanol group in one or both ends of a fluorinated alkylgroup. Specific examples of such compositions are described in JapaneseLaid-Open Patent Publication Nos. 2002-265866 and 2002-317152.

(3) Composition Containing Monomer Having Two or More EthylenicUnsaturated Groups and Fine Inorganic Particle Having a Hollow Structure

In another preferred example, the low refractive index layer contains alow refractive index particle and a binder. The low refractive indexparticle may be an organic or inorganic particle, and is preferably aparticle having an internal cavity. Specific examples of such hollowparticles include silica-based particles described in Japanese Laid-OpenPatent Publication No. 2002-079616 (see, e.g., Paragraphs [0041] to[0049]). The refractive index of the particle is preferably 1.15 to1.40, further preferably 1.20 to 1.30. The binder may be the monomerhaving two or more ethylenic unsaturated groups described above withrespect to the hard coat layer 122.

The polymerization initiator described above with respect to the hardcoat layer 122 is preferably added to the low refractive index layer(see, e.g., Paragraphs [0090] to [0093] of Japanese Laid-Open PatentPublication No. 2006-030740). In the case of using aradical-polymerizable compound, 1 to 10 parts by mass (preferably 1 to 5parts by mass) of the polymerization initiator may be used per 100 partsby mass of the compound.

An inorganic particle may jointly be used in the low refractive indexlayer. The particle diameter of the fine particle may be 15% to 150% ofthe thickness of the low refractive index layer to improve the abrasionresistance. The particle diameter is preferably 30% to 100% and furtherpreferably 45% to 60% of the thickness.

A known polysiloxane- or fluorine-based antifouling agent, lubricant, orthe like may be appropriately added to the low refractive index layer toimprove the antifouling property, water resistance, chemical resistance,lubricity, etc.

[High Refractive Index Layer/Middle Refractive Index Layer]

As described above, in the antireflection film 126, the high refractiveindex layer may be disposed between the low refractive index layer andthe hard coat layer 122 to improve the antireflection property.

The high and middle refractive index layers are preferably formed from ahardenable composition containing a fine inorganic high refractive indexparticle and a binder. The above-described fine inorganic highrefractive index particle for increasing the refractive index of thehard coat layer 122 may be used in the hardenable composition. Preferredexamples of the fine inorganic high refractive index particles includeinorganic compound particles (such as silica particles and TiO₂particles) and resin particles (such as acrylic particles, crosslinkedacrylic particles, polystyrene particles, crosslinked styrene particles,melamine resin particles, and benzoguanamine resin particles).

The high and middle refractive index layers may be preferably formed inthe following manner. The inorganic particle is dispersed in adispersion medium to prepare a dispersion liquid, and a binder precursor(such as an ionizing radiation-curable multifunctional monomer oroligomer to be hereinafter described), a photopolymerization initiator,and the like for forming a matrix are added thereto if necessary, toprepare a coating composition for the high and middle refractive indexlayers. Then, the coating composition for the high and middle refractiveindex layers is applied to the transparent film or the like, and theapplied composition is hardened by crosslinking or polymerizing theionizing radiation-curable compound (such as the multifunctional monomeror oligomer).

It is preferred that the binder of the high and middle refractive indexlayers is further crosslinked or polymerized with a dispersing agent inor after the process of applying the layer.

For example, the above preferred dispersing agent and the ionizingradiation-curable multifunctional or oligomer are crosslinked orpolymerized, whereby an anionic group of the dispersing agent isintroduced to the binder in the high and middle refractive index layers.The anionic group acts to maintain the dispersion state of the inorganicparticle in the binder in the high and middle refractive index layers,and the binder exhibits a film forming ability due to the crosslinked orpolymerized structure, whereby the high and middle refractive indexlayers containing the inorganic particle are improved in the physicalstrength, chemical resistance, and weather resistance.

The ratio of the binder in the high refractive index layer to the solidcontent of the coating composition for the layer is 5% to 80% by mass.

The ratio of the inorganic particle in the high refractive index layerto the layer is preferably 10% to 90% by mass, more preferably 15% to80% by mass, particularly preferably 15% to 75% by mass. Two or moretypes of the inorganic particles may be used in combination in the highrefractive index layer.

In the case of disposing the low refractive index layer on the highrefractive index layer, the refractive index of the high refractiveindex layer is preferably higher than that of the transparent film 130.

In the case of using the high refractive index layer as an opticalinterference layer, the thickness thereof is preferably 30 to 200 nm,more preferably 50 to 170 nm, particularly preferably 60 to 150 nm.

The high and middle refractive index layers preferably have a lowerhaze. The haze is preferably 5% or less, further preferably 3% or less,particularly preferably 1% or less.

The integrated reflectance of the antireflection film 126 having the lowrefractive index layer is preferably 3.0% or less, further preferably2.0% or less, most preferably 0.3% to 1.5%.

The surface free energy of the low refractive index layer is preferablyreduced to improve the antifouling property. Specifically, it ispreferred that a fluorine- or polysiloxane structure-containing compoundis used in the low refractive index layer. Alternatively, a separateantifouling layer containing the compound may be formed on the lowrefractive index layer.

Preferred examples of the polysiloxane structure-containing additivesinclude reactive group-containing polysiloxanes such as KF-100T,X-22-169AS, KF-102, X-22-37011E, X-22-164B, X-22-5002, X-22-173B,X-22-174D, X-22-167B, and X-22-161AS (trade names) available fromShin-Etsu Chemical Co., Ltd.; AK-5, AK-30, and AK-32 (trade names)available from Toagosei Co., Ltd.; and SILAPLANE FM0725 and SILAPLANEFM0721 (trade names) available from Chisso Corporation. Furthermore,silicone compounds described in Tables 2 and 3 of Japanese Laid-OpenPatent Publication No. 2003-112383 may be preferably used as theadditive. The ratio of the polysiloxane additive to the total solidcontent of the low refractive index layer is preferably 0.1% to 10% bymass, particularly preferably 1% to 5% by mass.

[Formation of Antireflection Film 126]

The antireflection film 126 may be formed by the following coatingmethod though the formation is not limited thereto.

(Preparation for Coating)

First, a coating liquid containing the component for forming each layersuch as the hard coat layer 122 and the antireflection layer 124 isprepared. In general, the coating liquid contains an organic solvent,whereby it is necessary that the water content of the liquid iscontrolled to 2% or less, and that the liquid is sealed to reduce thevolatilization of the solvent. The organic solvent is selected dependingon the material for each layer. A stirrer or a disperser isappropriately used for improving the homogeneity of the coating liquid.

The prepared coating liquid is preferably filtrated before theapplication to prevent application failure. A filter used in thefiltration preferably has a smaller pore diameter as long as thecomponent in the coating liquid is not removed. The filtration pressureis appropriately selected within a range of 1.5 MPa or less. Thefiltrated coating liquid is preferably subjected to an ultrasonicdispersion treatment immediately before the application to defoam thedispersion liquid and to maintain the dispersion state.

Before the application, the transparent film 130 may be subjected to aheat treatment for correcting a base deformation or a surface treatmentfor improving an application property or adhesion to the coating layer.Specific examples of the surface treatments include corona dischargetreatments, glow discharge treatments, flame treatments, acidtreatments, alkali treatments, and ultraviolet irradiation treatments.An undercoat layer may be preferably formed as described in JapaneseLaid-Open Patent Publication No. 07-333433.

A dust removal process is preferably carried out before the application.The process may be performed using a dust removal method described inParagraph [0119] of Japanese Laid-Open Patent Publication No.2010-032795. It is particularly preferred that the static electricity onthe transparent film 130 is removed before the dust removal process inview of increasing the dust removal efficiency and preventing attachmentof wastes. The electricity removal may be performed using a methoddescribed in Paragraph [0120] of Japanese Laid-Open Patent PublicationNo. 2010-032795. Furthermore, a method described in Paragraphs [0121]and [0123] of this document may be utilized to improve the flatness andadhesion of the transparent film 130.

(Application Process)

Each layer in the antireflection film 126 may be formed by the followingapplication method though the formation is not limited thereto. A knownapplication method may be used in the formation, and examples thereofinclude dip coating methods, air knife coating methods, curtain coatingmethods, roller coating methods, wire bar coating methods, gravurecoating methods, extrusion coating methods (die coating methods) (seeU.S. Pat. No. 2,681,294 and International Patent Publication No. WO05/123274), and microgravure coating methods. Among the methods, themicrogravure coating methods and the die coating methods are preferred.The microgravure coating method is described in Paragraphs [0125] and[0126] of Japanese Laid-Open Patent Publication No. 2010-032795, the diecoating method is described in Paragraphs [0127] and [0128] of thisdocument, and the methods can be used in this embodiment. It ispreferred that the die coating method is carried out at a coating rateof 20 m/minute or more from the viewpoint of productivity.

(Drying Process)

After the coating liquid is applied onto the transparent film 130 forthe antireflection film 126 directly or with another layer interposed,the resultant web is preferably conveyed to a heat zone to remove thesolvent.

The solvent may be removed by utilizing various drying techniques, andspecific examples thereof include those described in Japanese Laid-OpenPatent Publication Nos. 2001-286817, 2001-314798, 2003-126768,2003-315505, and 2004-034002, etc.

The drying process may be carried out in the drying zone under atemperature condition described in Paragraph [0130] of JapaneseLaid-Open Patent Publication No. 2010-032795 and a drying air conditiondescribed in Paragraph [0131] of this document.

(Hardening Process)

After or at a later stage of the drying process for removing thesolvent, each coating layer for the antireflection film 126 may beconveyed in the web state in a zone for hardening the coating layerunder an ionizing radiation and/or heat. The ionizing radiation is notparticularly limited and may be appropriately selected from ultraviolet,electron beam, near-ultraviolet, visible, near-infrared, infrared, andX-ray radiations, etc. depending on the type of the hardenablecomposition forming the coating layer. The ionizing radiation ispreferably the ultraviolet or electron beam radiation, and isparticularly preferably the ultraviolet radiation that can be easilyhandled and can readily emit a high energy.

An ultraviolet source for photopolymerizing an ultraviolet-hardeningcompound described in Paragraph [0133] of Japanese Laid-Open PatentPublication No. 2010-032795 and an electron beam described in Paragraph[0134] of this document may be used in this embodiment. Furthermore, anirradiation condition, an irradiation light intensity, and anirradiation time described in Paragraphs [0135] and [0138] of thisdocument may be used in this embodiment. In addition, film surfacetemperatures before and after the irradiation, an oxygen concentration,and a method for controlling the oxygen concentration described inParagraphs [0136], [0137], and [0139] to [0144] of this document may beused in this embodiment.

(Handling for Continuous Production)

The antireflection film 126 may be continuously produced by the steps ofcontinuously feeding the transparent film 130 from the roll, applyingand drying the coating liquid, hardening the applied coating, andrewinding the transparent film 130 having the hardened layer.

The steps may be carried out in each layer formation. Alternatively, aplurality of application zones, drying chambers, and hardening zones maybe formed in a so-called tandem structure, whereby a plurality of thelayers may be successively formed.

In the production of the antireflection film 126, it is preferred thatthe fine filtration of the coating liquid, the application process inthe application zone, and the drying process in the drying chamber arecarried out in a highly clean air atmosphere, and wastes and dusts onthe transparent film 130 are sufficiently removed before theapplication. The air cleanliness in the application and drying processesis preferably Class 10 (the number of particles having a size of 0.5 μmor more being 353 or less per m³) or higher, further preferably Class 1(the number being 35.5 or less per m³) or higher, in accordance with USFederal Standard 209E. It is preferred that also the processes otherthan the application and drying processes (such as the feeding andrewinding processes) are carried out under the high air cleanliness.

In view of improving the image sharpness, it is preferred that thesurface flatness and smoothness of the antireflection film 126 aremaximally increased, and in addition the sharpness of a transmittedimage is controlled. The transmitted image sharpness of theantireflection film 126 is preferably 60% or more. In general, thetransmitted image sharpness is a reference index indicating a blur levelof an image transmitted through a film. As the film has a larger valueof the transmitted image sharpness, the image transmitted through thefilm is sharper and better. The transmitted image sharpness ispreferably 70% or more, further preferably 80% or more.

The antireflection film 126 may be used as a viewer-side surface film onthe display device 108. The display devices 108 include various liquidcrystal displays, plasma displays, organic EL displays, and touchpanels. Depending on the characteristics of the outermost surface of thedisplay device 108 on which the antireflection film 126 is disposed,before the antireflection film 126 is attached to the touch panel 100,an adhesive layer may be formed on the back surface of the transparentfilm 130 (on which the coating layers are not formed), and the backsurface of the transparent film 130 may be saponified.

A technique described in Paragraphs [0149] to [0160] of JapaneseLaid-Open Patent Publication No. 2010-032795 may be used for saponifyingthe back surface of the transparent film 130.

The present invention may be appropriately combined with technologiesdescribed in the following patent publications and international patentpamphlets shown in Tables 1 and 2. The terms “Japanese Laid-OpenPatent”, “Publication No.”, “Pamphlet No.”, etc. are omitted.

TABLE 1 2004-221564 2004-221565 2007-200922 2006-352073 2007-1292052007-235115 2007-207987 2006-012935 2006-010795 2006-228469 2006-3324592009-21153 2007-226215 2006-261315 2007-072171 2007-102200 2006-2284732006-269795 2006-269795 2006-324203 2006-228478 2006-228836 2007-0093262006-336090 2006-336099 2006-348351 2007-270321 2007-270322 2007-2013782007-335729 2007-134439 2007-149760 2007-208133 2007-178915 2007-3343252007-310091 2007-116137 2007-088219 2007-207883 2007-013130 2005-3025082008-218784 2008-227350 2008-227351 2008-244067 2008-267814 2008-2704052008-277675 2008-277676 2008-282840 2008-283029 2008-288305 2008-2884192008-300720 2008-300721 2009-4213 2009-10001 2009-16526 2009-213342009-26933 2008-147507 2008-159770 2008-159771 2008-171568 2008-1983882008-218096 2008-218264 2008-224916 2008-235224 2008-235467 2008-2419872008-251274 2008-251275 2008-252046 2008-277428

TABLE 2 2006/001461 2006/088059 2006/098333 2006/098336 2006/0983382006/098335 2006/098334 2007/001008

EXAMPLES

The present invention will be described more specifically below withreference to Examples. Materials, amounts, ratios, treatment contents,treatment procedures, and the like, used in Examples, may beappropriately changed without departing from the scope of the invention.The following specific examples are therefore to be considered in allrespects as illustrative and not restrictive.

First Example

The surface resistance and the transmittance of each conductive sheetaccording to Examples 1 to 8 and Reference Examples 1 and 2 weremeasured, and the moire and the visibility were evaluated.

Examples 1 to 8 and Reference Examples 1 and 2 (Photosensitive SilverHalide Material)

An emulsion containing an aqueous medium, a gelatin, and silveriodobromochloride particles was prepared. The amount of the gelatin was10.0 g per 150 g of Ag, and the silver iodobromochloride particles hadan I content of 0.2 mol %, a Br content of 40 mol %, and an averagespherical equivalent diameter of 0.1 μm.

K₃Rh₂Br₉ and K₂IrCl₆ were added to the emulsion at a concentration of10⁻⁷ mol/mol-silver to dope the silver bromide particles with Rh and Irions. Na₂PdCl₄ was further added to the emulsion, and the resultantemulsion was subjected to gold-sulfur sensitization using chlorauricacid and sodium thiosulfate. The emulsion and a gelatin hardener wereapplied to the first transparent substrate 14A and the secondtransparent substrate 14B composed of a polyethylene terephthalate(PET). The applied silver amount was 10 g/m², and the Ag/gelatin volumeratio was 2/1.

The PET support had a width of 30 cm, and the emulsion was appliedthereto into a width of 25 cm and a length of 20 m. Both the edgeportions having a width of 3 cm were cut off to obtain a roll of aphotosensitive silver halide material having a width of 24 cm.

(Exposure)

To obtain Sample 1, an A4 (210 mm×297 mm) sized region of the firsttransparent substrate 14A was exposed in the pattern of the firstconductive sheet 10A in the first laminated conductive sheet 12A shownin FIGS. 1 and 4, and an A4 sized region of the second transparentsubstrate 14B was exposed in the pattern of the second conductive sheet10B in the first laminated conductive sheet 12A shown in FIGS. 4 and 6.To obtain Sample 2, an A4 (210 mm×297 mm) sized region of the firsttransparent substrate 14A was exposed in the pattern of the firstconductive sheet 10A in the second laminated conductive sheet 12B shownin FIGS. 9 and 10, and an A4 sized region of the second transparentsubstrate 14B was exposed in the pattern of the second conductive sheet10B in the second laminated conductive sheet 12B shown in FIGS. 9 and11. To obtain Sample 3, an A4 (210 mm×297 mm) sized region of the firsttransparent substrate 14A was exposed in the pattern of the firstconductive sheet 10A in the third laminated conductive sheet 12C shownin FIGS. 13 and 14, and an A4 sized region of the second transparentsubstrate 14B was exposed in the pattern of the second conductive sheet10B in the third laminated conductive sheet 12C shown in FIGS. 13 and15. The small lattices 18 had an arrangement pitch P of 200 μm, and themedium lattices 24 had an arrangement pitch of 2×P. In addition, thesmall lattices 18 had a conductive portion thickness of 2 μm and a widthof 10 μm. The exposure was carried out using a parallel light from alight source of a high-pressure mercury lamp and photomasks having theabove patterns.

(Development) Formulation of 1 L of Developer

Hydroquinone 20 g  Sodium sulfite 50 g  Potassium carbonate 40 g Ethylenediaminetetraacetic acid 2 g Potassium bromide 3 g Polyethyleneglycol 2000 1 g Potassium hydroxide 4 g pH Controlled at 10.3

Formulation of 1 L of Fixer

Ammonium thiosulfate solution (75%) 300 ml Ammonium sulfite monohydrate 25 g 1,3-Diaminopropanetetraacetic acid  8 g Acetic acid  5 g Aqueousammonia (27%)  1 g pH Controlled at 6.2

The exposed photosensitive material was treated with the above treatmentagents under the following treatment conditions using an automaticprocessor FG-710PTS manufactured by FUJIFILM Corporation. In thisprocess, a development treatment was carried out at 35° C. for 30seconds, a fixation treatment was carried out at 34° C. for 23 seconds,and then a water washing treatment was carried out for 20 seconds at awater flow rate of 5 L/min.

Example 1

In thus-obtained Samples 1 to 3, the conductive portions on the firstconductive sheets 10A and the second conductive sheets 10B (the firstconductive patterns 26A and the second conductive patterns 26B) had aline width of 1 pin, the small lattices 18 had a side length of 50 μm,and the large lattices (the first large lattices 16A and the secondlarge lattices 16B) had a side length of 3 mm.

Example 2

First and second conductive sheets of Example 2 were produced in thesame manner as in Example 1 except that the conductive portions had aline width of 3 μm and the small lattices 18 had a side length of 50 μmin Samples 1 to 3.

Example 3

First and second conductive sheets of Example 3 were produced in thesame manner as in Example 1 except that the conductive portions had aline width of 4 μm and the small lattices 18 had a side length of 50 μmin Samples 1 to 3.

Example 4

First and second conductive sheets of Example 4 were produced in thesame manner as in Example 1 except that the conductive portions had aline width of 5 μm and the small lattices 18 had a side length of 50 μmin Samples 1 to 3.

Example 5

First and second conductive sheets of Example 5 were produced in thesame manner as in Example 1 except that the conductive portions had aline width of 8 μm, the small lattices 18 had a side length of 150 μm,and the large lattices had a side length of 5 mm in Samples 1 to 3.

Example 6

First and second conductive sheets of Example 6 were produced in thesame manner as in Example 1 except that the conductive portions had aline width of 9 μm, the small lattices 18 had a side length of 150 μm,and the large lattices had a side length of 5 mm in Samples 1 to 3.

Example 7

First and second conductive sheets of Example 7 were produced in thesame manner as in Example 1 except that the conductive portions had aline width of 10 μm, the small lattices 18 had a side length of 300 μm,and the large lattices had a side length of 6 mm in Samples 1 to 3.

Example 8

First and second conductive sheets of Example 8 were produced in thesame manner as in Example 1 except that the conductive portions had aline width of 15 μm, the small lattices 18 had a side length of 400 μm,and the large lattices had a side length of 10 mm in Samples 1 to 3.

Reference Example 1

First and second conductive sheets of Reference Example 1 were producedin the same manner as in Example 1 except that the conductive portionshad a line width of 0.5 μm and the small lattices 18 had a side lengthof 40 μm in Samples 1 to 3.

Reference Example 2

First and second conductive sheets of Reference Example 2 were producedin the same manner as in Example 1 except that the conductive portionshad a line width of 20 μm, the small lattices 18 had a side length of500 μm, and the large lattices had a side length of 10 mm in Samples 1to 3.

[Evaluation]

In each of Examples 1 to 8 and Reference Examples 1 and 2, the surfaceresistance, moire, and visibility were evaluated. The evaluation resultsare shown in Table 3.

(Surface Resistance Measurement)

In each of the first conductive sheets 10A and the second conductivesheets 10B, the surface resistivity values of optionally selected 10areas were measured by LORESTA GP (Model No. MCP-T610) manufactured byDia Instruments Co., Ltd. utilizing an in-line four-probe method (ASP),and the average of the measured values was obtained to evaluate thesurface resistivity uniformity.

(Transmittance Measurement)

The transmittance of each of the first conductive sheets 10A and thesecond conductive sheets 10B was measured by a spectrophotometer toevaluate the transparency.

(Moire Evaluation)

In each of Examples 1 to 8 and Reference Examples 1 and 2, the firstconductive sheet 10A was stacked on the second conductive sheet 10B toobtain a laminated conductive sheet. The laminated conductive sheet wasattached to a display screen 110 a of a display device 108 to obtain atouch panel 100. The touch panel 100 was fixed to a turntable, and thedisplay device 108 was operated to display a white color. The moire ofthe laminated conductive sheet was visually observed and evaluated whileturning the turntable within a bias angle range of −20° to +20°.

The moire was observed at a distance of 1.5 m from the display screen ofthe liquid crystal display device. The laminated conductive sheet wasevaluated as “Excellent” when the moire was not visible, as “Fair” whenthe moire was slightly visible to an acceptable extent, or as “Poor”when the moire was highly visible.

(Visibility Evaluation)

In a condition where the touch panel 100 was fixed to the turntable andthe display device 108 was operated to display the white color, beforethe moire evaluation, whether a thickened line or a black point wasformed or not on the touch panel 100 and whether boundaries between thefirst large lattices 16A and the second large lattices 16B in the touchpanel 100 were visible or not were observed by the naked eye.

TABLE 3 Side Line width Side length of length of conductive of smalllarge Surface portion lattice lattice resistance Transmittance MoireVisibility (μm) (μm) (mm) (Ω/sq) (%) evaluation evaluation Reference 0.540 3 10 90 Fair Fair Example 1 Example 1 1 50 3 5 90 Excellent ExcellentExample 2 3 50 3 5 75 Excellent Excellent Example 3 4 50 3 5 86Excellent Excellent Example 4 5 50 3 5 87 Excellent Excellent Example 58 150 5 5 86 Excellent Excellent Example 6 9 150 5 5 86 ExcellentExcellent Example 7 10 300 6 5 86 Excellent Excellent Example 8 15 40010 5 85 Excellent Excellent Reference 20 500 10 4 83 Fair Fair Example 2

(Evaluation Result)

It was found that the conductive sheets of Examples 1 to 8 had a surfaceresistance of 5 ohm/sq, and thereby could be satisfactory used in theA4-sized projected capacitive touch panel. In addition, the conductivesheets of Examples 1 to 8 were excellent in the transmittance, moire,and visibility.

Second Example

In Second Example, the moire and the visibility of each touch panel ofReference Examples 11 to 13 and Examples 11 to 30 were evaluated. Thecomponents and evaluation results of Reference Examples 11 to 13 andExamples 11 to 30 are shown in Table 4.

Example 11 (Photosensitive Silver Halide Material)

An emulsion containing an aqueous medium, a gelatin, and silveriodobromochloride particles was prepared. The amount of the gelatin was10.0 g per 150 g of Ag, and the silver iodobromochloride particles hadan I content of 0.2 mol %, a Br content of 40 mol %, and an averagespherical equivalent diameter of 0.1 μm.

K₃Rh₂Br₉ and K₂IrCl₆ were added to the emulsion at a concentration of10⁻⁷ mol/mol-silver to dope the silver bromide particles with Rh and Irions. Na₂PdCl₄ was further added to the emulsion, and the resultantemulsion was subjected to gold-sulfur sensitization using chlorauricacid and sodium thiosulfate. The emulsion and a gelatin hardener wereapplied to the first transparent substrate 14A and the secondtransparent substrate 14B composed of a polyethylene terephthalate(PET). The applied silver amount was 10 g/m², and the Ag/gelatin volumeratio was 2/1.

The PET support had a width of 30 cm, and the emulsion was appliedthereto into a width of 25 cm and a length of 20 m. Both the edgeportions having a width of 3 cm were cut off to obtain a roll of aphotosensitive silver halide material having a width of 24 cm.

(Exposure)

An A4 (210 mm×297 mm) sized region of the first transparent substrate14A was exposed in the pattern of the first conductive sheet 10A in thefourth laminated conductive sheet 12D shown in FIGS. 17 and 19, and anA4 sized region of the second transparent substrate 14B was exposed inthe pattern of the second conductive sheet 10B in the fourth laminatedconductive sheet 12D shown in FIGS. 17 and 20. The exposure was carriedout using a parallel light from a light source of a high-pressuremercury lamp and photomasks having the above patterns.

(Development) Formulation of 1 L of Developer

Hydroquinone 20 g  Sodium sulfite 50 g  Potassium carbonate 40 g Ethylenediaminetetraacetic acid 2 g Potassium bromide 3 g Polyethyleneglycol 2000 1 g Potassium hydroxide 4 g pH Controlled at 10.3

Formulation of 1 L of Fixer

Ammonium thiosulfate solution (75%) 300 ml Ammonium sulfite monohydrate 25 g 1,3-Diaminopropanetetraacetic acid  8 g Acetic acid  5 g Aqueousammonia (27%)  1 g pH Controlled at 6.2

The exposed photosensitive material was treated with the above treatmentagents under the following treatment conditions using an automaticprocessor FG-710PTS manufactured by FUJIFILM Corporation. In thisprocess, a development treatment was carried out at 35° C. for 30seconds, a fixation treatment was carried out at 34° C. for 23 seconds,and then a water washing treatment was carried out for 20 seconds at awater flow rate of 5 L/min.

(Touch Panel)

The first conductive sheet 10A was stacked on the second conductivesheet 10B to obtain a laminated conductive sheet, and the laminatedconductive sheet was attached to a display screen of a liquid crystaldisplay device to produce a touch panel of Example 11. In Example 11, asshown in Table 4, the conductive portions (the first conductive patterns26A, the first dummy patterns 20A, the second conductive patterns 26B,and the second dummy patterns 20B) had a line width of 5 μm, the smalllattices 18 had a side length of 50 μm, and the large lattices (thefirst large lattices 16A and the second large lattices 16B) had a sidelength of 3 mm. In Example 11, the displacement in the third and fourthdirection (hereinafter referred to as the shift length) was 2.5 μm.

Examples 12 to 14

Touch panels of Examples 12, 13, and 14 were produced in the same manneras in Example 11 except that the shift lengths were 5 μm, 10 μm, and 25μm, respectively.

Example 15

A touch panel of Example 15 was produced in the same manner as inExample 11 except that the conductive portions had a line width of 7 μm,the small lattices 18 had a side length of 250 μm, the large latticeshad a side length of 5 mm, and the shift length was 50 μm.

Example 16

A touch panel of Example 16 was produced in the same manner as inExample 11 except that the conductive portions had a line width of 8 μm,the small lattices 18 had a side length of 250 μm, and the largelattices had a side length of 5 mm.

Examples 17 to 22

Touch panels of Examples 17, 18, 19, 20, 21, and 22 were produced in thesame manner as in Example 16 except that the shift lengths were 4 μm, 10μm, 30 μm, 50 μm, 100 μm, and 125 μm, respectively.

Example 23

A touch panel of Example 23 was produced in the same manner as inExample 16 except that the conductive portions had a line width of 9 μm,and the shift length was 50 μm.

Example 24

A touch panel of Example 24 was produced in the same manner as inExample 11 except that the conductive portions had a line width of 10μm, the small lattices 18 had a side length of 300 μm, and the largelattices had a side length of 6 mm.

Examples 25 to 30

Touch panels of Examples 25, 26, 27, 28, 29, and 30 were produced in thesame manner as in Example 24 except that the shift lengths were 4 μm, 10μm, 30 μm, 50 μm, 100 μm, and 150 μm, respectively.

Reference Examples 11 to 13

A touch panel of Reference Example 11 was produced in the same manner asin Example 11 except that the shift length was 0 μm.

A touch panel of Reference Example 12 was produced in the same manner asin Example 16 except that the shift length was 0 μm.

A touch panel of Reference Example 13 was produced in the same manner asin Example 24 except that the shift length was 0 μm.

TABLE 4 Line width of Side length Side length conductive of small oflarge Shift portion lattice lattice length Moire Visibility (μm) (μm)(mm) (μm) evaluation evaluation Reference 5 50 3 0 Poor ExcellentExample 11 Example 11 5 50 3 2.5 Fair Excellent Example 12 5 50 3 5 Fairor Excellent Excellent Example 13 5 50 3 10 Excellent Excellent Example14 5 50 3 25 Excellent Excellent Example 15 7 250 5 50 ExcellentExcellent Reference 8 250 5 0 Poor Excellent Example 12 Example 16 8 2505 2.5 Fair Excellent Example 17 8 250 5 4 Fair or Excellent ExcellentExample 18 8 250 5 10 Excellent Excellent Example 19 8 250 5 30Excellent Excellent Example 20 8 250 5 50 Excellent Excellent Example 218 250 5 100 Excellent Excellent Example 22 8 250 5 125 Fair or FairExcellent Example 23 9 250 5 50 Excellent Excellent Reference 10 300 6 0Poor Excellent Example 13 Example 24 10 300 6 2.5 Fair Excellent Example25 10 300 6 4 Fair or Excellent Excellent Example 26 10 300 6 10Excellent Excellent Example 27 10 300 6 30 Excellent Excellent Example28 10 300 6 50 Excellent Excellent Example 29 10 300 6 100 ExcellentExcellent Example 30 10 300 6 150 Fair or Fair Excellent

[Evaluation] (Moire Evaluation)

The touch panel was fixed to a turntable, and the liquid crystal displaydevice was operated to display a white color. The moire of the touchpanel was visually observed and evaluated while turning the turntablewithin a bias angle range of −20° to +20°.

The moire was observed at a distance of 1.5 m from the display screen ofthe liquid crystal display device. The touch panel was evaluated as“Excellent” when the moire was not visible, as “Fair” when the moire wasslightly visible to an acceptable extent, or as “Poor” when the moirewas highly visible.

(Visibility Evaluation)

In a condition where the touch panel was fixed to the turntable and theliquid crystal display device was operated to display the white color,before the moire evaluation, whether a thickened line or a black pointwas formed or not on the touch panel was observed by the naked eye.

(Evaluation Results)

The touch panels were generally excellent in the visibility though a fewthickened lines and black points were observed only in Examples 22 and30.

The moire was highly visible in Reference Examples 11 to 13. Incontrast, satisfactory moire evaluation results were obtained in allExamples 11 to 30. The moire was not visible in Examples 13 to 15, 18 to21, 23, and 26 to 29, the moire was only slightly visible to anacceptable extent in Examples 11, 16, and 24, and the moire was at anintermediate level between Fair and Excellent in Examples 12, 17, 22,25, and 30.

Incidentally, touch panels, which were produced in the same manner as inReference Examples 11 to 13 and Examples 11 to 30 except that the firstconductive part 13A was formed on one main surface of the firsttransparent substrate 14A and the second conductive part 13B was formedon the other main surface of the first transparent substrate 14A asshown in FIG. 18B, exhibited the same evaluation results.

Third Example

Projected capacitive touch panels were produced using the laminatedconductive sheets of Examples 1 to 8 and 11 to 30 respectively. Wheneach of the touch panels was operated by a finger touch, it exhibited ahigh response speed and an excellent detection sensitivity. Furthermore,when two or more points were touched, the touch panel exhibited the sameexcellent properties. Thus, it was confirmed that the touch panel wascapable of multi-touch detection.

It is to be understood that the conductive sheet, the conductive sheetusing method, and the touch panel of the present invention are notlimited to the above embodiments, and various changes and modificationsmay be made therein without departing from the scope of the invention.

1. A conductive member comprising a first conductive part and a secondconductive part, wherein the first conductive part contains two or morefirst conductive patterns and a first dummy pattern, the firstconductive patterns each extend in a first direction and are arranged ina second direction perpendicular to the first direction, the first dummypattern contains a plurality of first auxiliary wires arranged aroundthe first conductive patterns, the second conductive part contains twoor more second conductive patterns and a second dummy pattern, thesecond conductive patterns each extend in the second direction and arearranged in the first direction, the second dummy pattern contains aplurality of second auxiliary wires arranged around the secondconductive patterns, the first conductive patterns and the secondconductive patterns are insulated, the first conductive patterns and thesecond conductive patterns are crossed as viewed from above, anddisplaced from each other in a direction different from the firstdirection and from the second direction, the first dummy pattern and thesecond dummy pattern overlap with each other to form a combined patternbetween the first conductive patterns and the second conductivepatterns, and the first auxiliary wires and the second auxiliary wiresare not perpendicularly crossed in the combined pattern.
 2. Theconductive member according to claim 1, wherein the first conductivepatterns and the second conductive patterns contain a thin wire having aline width of 15 μm or less.
 3. A touch sensor comprising the conductivemember according to claim
 1. 4. A touch panel comprising the touchsensor according to claim
 3. 5. A conductive member comprising a firstconductive part and a second conductive part, wherein the firstconductive part contains two or more first conductive patterns and afirst dummy pattern, the first conductive patterns each extend in afirst direction and are arranged in a second direction perpendicular tothe first direction, the first dummy pattern contains a plurality offirst auxiliary wires arranged around the first conductive patterns, thesecond conductive part contains two or more second conductive patternsand a second dummy pattern, the second conductive patterns each extendin the second direction and are arranged in the first direction, thesecond dummy pattern contains a plurality of second auxiliary wiresarranged around the second conductive patterns, the first conductivepatterns and the second conductive patterns are insulated, the firstconductive patterns and the second conductive patterns are crossed asviewed from above, the first dummy pattern and the second dummy patternoverlap with each other to form a combined pattern between the firstconductive patterns and the second conductive patterns, the firstauxiliary wires and the second auxiliary wires are not perpendicularlycrossed in the combined pattern, the first conductive patterns eachcontain two or more first large lattices connected in series in thefirst direction, the second conductive patterns each contain two or moresecond large lattices connected in series in the second direction, thefirst large lattices and the second large lattices each contain acombination of two or more small lattices, the first dummy patternseparated from the first large lattices is formed around a side of thefirst large lattices, the second dummy pattern separated from the secondlarge lattices is formed around a side of the second large lattices, andthe first conductive part or the second conductive part is displaced byat most ½ of an arrangement pitch of the small lattices.
 6. Theconductive member according to claim 5, wherein the first conductivepatterns and the second conductive patterns contain a thin wire having aline width of 15 μm or less.
 7. A touch sensor comprising the conductivemember according to claim
 5. 8. A touch panel comprising the touchsensor according to claim
 5. 9. A conductive member comprising a firstconductive part and a second conductive part, wherein the firstconductive part contains two or more first conductive patterns and afirst dummy pattern, the first conductive patterns each extend in afirst direction and are arranged in a second direction perpendicular tothe first direction, the first dummy pattern contains a plurality offirst auxiliary wires arranged around the first conductive patterns, thesecond conductive part contains two or more second conductive patternsand a second dummy pattern, the second conductive patterns each extendin the second direction and are arranged in the first direction, thesecond dummy pattern contains a plurality of second auxiliary wiresarranged around the second conductive patterns, the first conductivepatterns and the second conductive patterns are insulated, the firstconductive patterns and the second conductive patterns are crossed asviewed from above, the first dummy pattern and the second dummy patternoverlap with each other to form a combined pattern between the firstconductive patterns and the second conductive patterns, the firstauxiliary wires and the second auxiliary wires are not perpendicularlycrossed in the combined pattern, the first conductive patterns eachcontain two or more first large lattices connected in series in thefirst direction, the second conductive patterns each contain two or moresecond large lattices connected in series in the second direction, thefirst large lattices and the second large lattices each contain acombination of two or more small lattices, the first dummy patternseparated from the first large lattices is formed around a side of thefirst large lattices, the second dummy pattern separated from the secondlarge lattices is formed around a side of the second large lattices, anda first axis line of the first auxiliary wire and a second axis line ofthe second auxiliary wire are arranged approximately in parallel in thecombined pattern, and a distance between the first axis line and thesecond axis line is at least of a smaller line width among line widthsof the first auxiliary wire and the second auxiliary wire and at most ½of the arrangement pitch of the small lattices.
 10. The conductivemember according to claim 9, wherein the first conductive patterns andthe second conductive patterns contain a thin wire having a line widthof 15 μm or less.
 11. A touch sensor comprising the conductive memberaccording to claim
 9. 12. A touch panel comprising the touch sensoraccording to claim
 11. 13. A conductive member comprising a firstconductive part and a second conductive part, wherein the firstconductive part contains two or more first conductive patterns and afirst dummy pattern, the first conductive patterns each extend in afirst direction and are arranged in a second direction perpendicular tothe first direction, the first dummy pattern contains a plurality offirst auxiliary wires arranged around the first conductive patterns, thesecond conductive part contains two or more second conductive patternsand a second dummy pattern, the second conductive patterns each extendin the second direction and are arranged in the first direction, thesecond dummy pattern contains a plurality of second auxiliary wiresarranged around the second conductive patterns, the first conductivepatterns and the second conductive patterns are insulated, the firstconductive patterns and the second conductive patterns are crossed asviewed from above, the first dummy pattern and the second dummy patternoverlap with each other to form a combined pattern between the firstconductive patterns and the second conductive patterns, the firstauxiliary wires and the second auxiliary wires are not perpendicularlycrossed in the combined pattern, and when a third direction is definedas a direction bisecting an angle between the first and seconddirections, and a fourth direction is defined as a directionperpendicular to the third direction, the first conductive part or thesecond conductive part is displaced by a shift length from a standardposition at least in the third direction, the shift length being atleast ½ of a smaller line width among line widths of the first auxiliarywire and the second auxiliary wire and at most 100 μm.
 14. Theconductive member according to claim 13, wherein the first conductivepatterns and the second conductive patterns contain a thin wire having aline width of 15 μm or less.
 15. A touch sensor comprising theconductive member according to claim
 13. 16. A touch panel comprisingthe touch sensor according to claim 15.